This one is so strange i had to post it because sometimes the feedback here is amazingly good:

Oddly painful skin like it is sore or burned but there is nothing to see or notice to the touch.

There has been no exposure to the sun or anything consistently chemical in nature,

on one side of the upper back/shoulder on and off for weeks/months, very strange, very bizarre.

Any clues? any bright ideas? thanks

Sounds like post herpetic neuralgia that can persist or recur sometimes without the accompanying rash every time.

May be worthwhile to take some acyclovir at the next onset; if this reduces the pain and duration, it probably is PHN.

Thanks i will look that up.

I think it gets irritated from the cloths i wear, i am hoping it is only that.

I may try some fresh aloe too.

That often works wonders.

Sounds like Shingles to me and post herpetic neuralgia as FBN states. You probably had a minor bout of Shingles so you didn't notice and this is the left overs pain from the nerves that were damaged by the Shingles virus

Interesting, i will look that up too.

Odd there is nothing to see or touch, i think it is from the cloths rubbing/irritating but cant be sure.