Valerian can be VERY dangerous.  See the video on YouTube by chubbyemu ( an MD.)

There is a medicine for tobacco cessation.  It is known by several names: Zyban, Quomem or GSK Thailand's Buprenorphine XL.  Your local pharmacy can order it for you.  Be sure to start at the lowest dose (160.). It may take 2-3 days for your blood level to obtain the desired level.  If it doesn't work for you, stop it after the first few doses.  Wickipedia says that it is an opioid.  It isn't exactly.  its mechanism isn't understood.   I hope that it works for you.  It worked like a charm for me.

On 11/3/2020 at 6:52 AM, amelibeli75 said:

I quit smoking about a year ago and since then have had HORRIBLE insomnia. I can't fall asleep...........................

Just a thought - had you smoked for a long time and stopped suddenly?  Some people seem to be able to cope with that but many long term smokers report quite bad side effects after stopping suddenly.

I'm considering stopping after a hell of a long time and spoke to my doctor about it.  He told me that I could possibly have severe effects if I stopped suddenly and recommended a gradual approach.  I suppose it makes sense really, if your body has been used to chemicals etc. for 40+ years and you suddenly withdraw them, there could be problems.

After a year it has nothing to do with nicotine withdrawal.  You're well over that stage.
If you have been taking benzodiazapines for sleep (diazapam, lorazapam, etc) for awhile then perhaps you have developed a tolerance to the sedative.  One of the symptoms of tolerance is - anxiety and insomnia, and the anxiety could cause the racing heart.
I'd suggest seeing a cardiologist as well as getting off of the sleeping pills if they are benzodiazapines (https://www.benzofree.org/info/ashton/).

I personally do cold water training (read up on cold shock proteins) which induces bradycardia (slowing of the heart).  Also putting your face in cold water will do the same (mammalian dive reflex).  But back to the talking about doctors.  Don't do any of this without talking to a cardiologist.
Make sure you don't have heart issues (damage) that are causing the rapid racing heart.  That isn't normal and it has nothing to do with nicotine withdrawal from 1 year ago although depending on how long you smoked, the smoking itself may have damaged your heart.  Smoking sucks.  Been there, done that, but quit at 25 because smoking and athletics didn't mix.  As far as I'm concerned it killed both my parents.

Close post as author has stated issue was solved----about 4--5 posts down from his post.

21 hours ago, Tony125 said:

Close post as author has stated issue was solved----about 4--5 posts down from his post.

Your not a moderator. Dont try to be something that your not....

Can OP give us an update? What caused his problem?

Whatever you do, don't allow yourself to become addicted to prescription sleep meds. They'll stop working & you're still addicted.

Suggestions above are excellent. You might want to try Melatonin. Regular release if you have trouble falling asleep, time-release if you have frequent arousals. Start low, 1-3mg should help.

I'd also suggest avoid cardio workouts. Yoga is quite enough.

Eat healthy, drink lots of water. No caffeine, no alcohol.

Regular bedtime & rising. Dark bedroom, preferably alone in bed. No screens an hour before lights out.

You'll be no fun (like me) but, if you're lucky, you'll get a night's rest most nights.

I totally get where you're coming from. When I quit smoking a while back, my sleep went downhill too. I had issues with insomnia and even had a racing heart at night, so I had to start taking beta blockers just to keep it under control. I also noticed that anything that got my heart rate up, like exercise or even getting too excited, would ruin my sleep that night. For me, trying to keep my evenings as calm as possible helped a bit – I’d avoid anything too stimulating before bed, like movies or intense conversations. It wasn’t an instant fix, but it made things a bit more manageable. It sounds like the adrenal thing could be playing a big role, and maybe talking to your doc about ways to manage that could help.

On 11/3/2020 at 6:52 AM, amelibeli75 said:

I quit smoking about a year ago and since then have had HORRIBLE insomnia. I can't fall asleep on my own without sleep aids. When I do finally fall asleep, even with the sleep aids/prescription sleeping pills, I tend to wake up 4 or 5 hours later with my heart pounding for no reason. I had to be put on beta blockers for my racing heart. Without them, my heart rate would be over 100 beats per minute all day. Also, if I exercise, it makes things worse. Any thing that gets my heart rate up such as watching a scary movie, laughing too hard, exercising, etc will cause me to not sleep that night. My doc says it's because my adrenal glands are on hyper-drive since I quit nicotine. Anyone else having these problems?

Take Magnesium threonate if it does not inteact with any meds..there is also loads of magnesium in Spinach etc.....mag helps so many things...sleep/ mental balance/heart.

14 minutes ago, cheskakim said:

I totally get where you're coming from. When I quit smoking a while back, my sleep went downhill too. I had issues with insomnia and even had a racing heart at night, so I had to start taking beta blockers just to keep it under control. I also noticed that anything that got my heart rate up, like exercise or even getting too excited, would ruin my sleep that night. For me, trying to keep my evenings as calm as possible helped a bit – I’d avoid anything too stimulating before bed, like movies or intense conversations. It wasn’t an instant fix, but it made things a bit more manageable. It sounds like the adrenal thing could be playing a big role, and maybe talking to your doc about ways to manage that could help.

it's a post from 2021...he solved it.