Gum Blister - PAINFUL

Hi guys,

First off.. Long time reader, first time poster!! Now, down to the detail. I had 2 fillings done on 2 teeth on the left lower jaw. Now, occasionally (and especially at present), I have a swollen gum around these 2 teeth with fillings and a blister that is the same colour as the gum under them. This cause what is usually minor pain along the left side of my jaw so I wouldn't worry about it usually but at present it's rather intense. I found sm33 helps a little however there must be a reason it's happening in the first place!!
I'm paranoid about going back to the dentist because when he did the fillings, I could feel the drill as he drilled. It put me off greatly.

Any advice?