Pain after getting cavities filled.?

I had 18 cavities filled in one day. My mouth hurts now. My teeth and I guess the gums ache. It feels like when I had braces after they adjusted or tightened the braces. So it's been 3 weeks since I had the work done. I've gone back to the dentist 3 times. The first two times they adjusted my bite and the third time they didn't see any problems and just told me that I'd hurt for awhile because I had so much done. I'm trying to be patient but I have to take Tylenol or ibuprofen every 4-5 hours to not be in pain. Three weeks of that is kind of hard on my stomach. So my question is what can I do to help with the pain? And does anyone have an opinion on whether or not this is normal?