I have a sore on the inside of my left cheek, right above the gums. it looks a bit like pimple, and it has been causing a lot of pain for the past two days, it also feels like a toothache. it has also made it difficult to eat. what could this be?

Fistula: It may be a draining abscess. Cause could be periodontal or endodontic in nature. Either way it needs to be evaluated by a dentist for proper treatment.

Pimple: Probably a draining abscess, an infection that has created a drainage tract. This can be from infected tooth/teeth and or infected gums/bone. Oral infections can be quite virulent, spreading rapidly to other organ systems. Important that you see your General Dentist immediately. He/she will decide whether to treat or refer.