I had a tooth pulled before back when I was like 9. They used the gas mask thing on me. I only remember crying and trying to run away from the dentists before they grabbed me and held me down while putting that mask on me, next thing I know I'm laying on some bed, mouth swollen and hurting like hell with no idea what the hell just happened.
Fast forward 10 years, when I was in AIT training for the Army they wanted everyone to get their wisdom teeth pulled before you graduated. I got all 3 of my teeth pulled on the same day, and I received a medical profile to be put on bed rest for 4 days. Mostly because the school I attended required operating heavy equipment, which isn't smart to do when your drugged up. I didn't tell my platoon sergeant about my profile and kept going to classes (Because if you miss more than 2 days of classes you'll get recalled and end up staying in training for another month or 2.) Annnd it sucked, but that's only because I had to work after I had them pulled.....And because I used chewing tobacco as soon as I walked out of the dental office (Big mistake in terms of pain, but totally worth it). I'm guessing you won't be doing that, so it shouldn't be so bad for you.
Overall, it's going to hurt (But not all the time, you'll be on pain medication) and it's going to suck, but it's not as bad as people make it out too be. You'll be fine. Oh yeah, I know not all dentists offer this, but if possible, I would recommend being getting gassed, at least you don't have to be conscious while they pull them. Being conscious for it sucks lol)