I recently got fillings and they don't hurt like earlier ones I got. HELP?!

I recently got fillings and they don't hurt like earlier ones I got. HELP?

I went about a week and a half ago to the dentist and got some cavities on the right side of my mouth filled. They were and still are very, VERY sensitive to sweets, hot, and cold food items. Even water.
I usually get a throbbing pain and sometimes it comes when I'm going to sleep even without eating sweet, cold or hot stuff.

I then got some cavities filled on the left side of my mouth two days ago and they don't hurt in the slightest. But the right side of my mouth still hurts...in particular two teeth, one on the top and one on the bottom.

I'm not asking how to solve the pain but rather the REASON for the pain...it hurts...

I told the dentist about the pain before I got the cavities on the left side fixed and he just said that I would have a painful reaction to those foods and ended it there.

I need to know why. I checked my teeth and I have no cracks or anything of the sort. My gums are fine.

It could be that the fillings were left high, that is certainly what I would check first. It could also be, if the fillings were composite or white, that there is not a good bond and they may need to be redone. Most likely however, it sounds like a pulpitis, which is an inflammation of the nerve of the tooth. This may be because the fillings were deep and quite close to the nerve. Ultimately, the teeth may need to have a root canal or be removed. Whenever you go digging around inside someone's tooth removing tooth decay this can happen.