First, I don’t think it will be just one tooth because of the symmetry of the mouth. It will probably be at least two, and typically is four (2 on top, 2 on bottom).
They will most likely give you local anesthesia and you won’t feel a thing, except for the needle which I’ve been told really isn’t a big deal at all. They’ll probably give you something for pain to take home with you and use after the anesthesia wears off. I had four wisdom teeth out all at once, which I’ve been told is more painful and complex than taking any other teeth out for a number of reasons. I was sedated and don’t even remember the surgery (they will likely not want to risk sedation on your teeth, though – there is a small chance you won’t wake up). Afterwards, I let the anesthesia wear off (I was curious), and it HURT LIKE A BITCH. It made my eyes well up with tears because it stung so bad. I took Vicodin for the rest of the weekend and was fine. I am amazed by how Vicodin totally blocks the pain sensation. You’ll be fine.
One thing you should consider is rapid palatal expansion (RPE for short). Instead of pulling your perfectly good teeth out, they non-surgically separate the two halves of your upper jaw and let bone fill in the space. I’ve read it has to be surgically done in adults to work, but know from personal experience this is not true! I’m still trying to get to the bottom of the discrepancy. I had pretty bad crowding on the bottom – I talked to two orthodontists and both said RPE wouldn’t work for me and that extraction was a must. Well, I had RPE and my teeth are straight (I am a couple months away from getting braces off). I am planning on trying to see one of the two orthos that said it was not possible to let her do a “peer review” of my ortho’s work.
I’m not sure if it is easier or less painful to go the RPE route. Instead of a single incident of serious pain, you have mild discomfort over a long period of time. The expansion appliance gave me a mild speech impediment since it obstructed the natural path of my tongue for a few months (which I figured was trivial since I plan to live 80 more years). For me, it was a combination of curiosity (of whether or not it would really work), practicality (not seeing any reason to waste 4 perfectly good teeth), and aesthetic (when you have 4 teeth pulled due to crowding and a narrow jaw, your smile may have dark gaps on the side [compare this to this].
There is only one orthodontist in my state that does RPE on adults. One of the other 2 orthos I saw said each ortho has their own method that they are comfortable with, and thus prefers to go with that. My ortho said he doesn’t always do RPE, in a few cases extraction really is necessary. What it sounds like to me is that most dentists don’t get training in RPE and therefore only know how to extract four teeth to straighten. To me, an orthodontist worth paying is well versed in all methods that work and knows when to apply each one.