What whippetgirl said makes sense. I had some dental work done over a period of time by a student at the dental "college", supervised by his professor of course (and gawped at by tons of other students, but that's part of the game), and anyway - to begin with I was pretty tense and disliked getting the anesthetic, but after a while I got pretty relaxed about it.

That's when I noticed that sometimes I'd react as if I'd been really scared - jittery, heart racing, "weak" elbows and knees - even though I felt mentally fine. I mentioned it, and when I was told that there was adrenaline in the anesthetic (helps reduce bleeding, I believe he said) it all fell into place. I get the exact same "rush" when I almost slip on my bike, for example See, even got this bike-related.

I've never had the eyesight problem, though, and I can imagine it must be quite scary.