Oh I hate the dentist! I had a similar experience. I went for something else and then the dentist said "Oh you need fillings in both upper back teeth" Even though I had zero pain. Then she continued to drill away for what seemed like hours and then says "It's quite a large hole and I've had to fill it a fair bit. If you get any pain you'll have to come back and we'll take it out" Then it started to hurt a few months later WTF? It's like she MADE the hole

I really feel for you, the dentist is horrible!