I had exactly the same experience, although I had a tooth abcess on the tooth that was extracted had infected through the jaw to my sinus's and required two weeks antibiotics before they removed (I'd already had two root canals on that tooth that cost a fortune so it might as well been made of gold :) ). Then same with the Amoxycillin after they extracted the molar. All went well in the end, I'm cautious to take antibiotics unless needed, but had not much choice this time around. It's my first implant, and the entire procedure when completed in three weeks will have taken a total 5 months (I believe it should have been 4, for some reason they extended a visit by 1 month). All has gone well and I wish you well with your treatment.