You sound like you've had a similar trip to me so far! My smear results were only borderline (mild as possible changes) but they test for the HPV virus now and my test came back positive for a high risk strain of HPV. That's why I got referred to colposcopy, and I suspect you might be the same. Did your letter say anything about HPV? As far as I understand it, whatever the smear result, if they find high risk HPV it's off to colposcopy for you!
They also took biopsies at my colposcopy. I did remember to ask the consultant how she thought it looked and she said CIN1 (mild) or CIN2 (moderate) changes, but the biopsy will confirm properly. The biopsy results came back as CIN2.
Your doctor sounds kind, like mine. Mine suggested that I have the treatment for it under general, but I decided to try local as I'd never had a GA and was worried about how I would recover. It didn't go well for me, though - 2 attempts to do the local anaesthetic and both times it was soooo painful. In the end we had to give up on that idea, and I had it done under GA last Friday.
I am also very very anxious about anything medical, but can honestly say having it done under general was fine. You fall asleep and when you wake up it's all over. Please try not to worry too much - if you have it done that way, it's really not too bad.
Best of luck and hope that they sort you out quickly