Hi Seda Bug:

What does it look like? I had a strange reddish pimple-looking thing that came up on the inside of my cheek several weeks ago, and like you, I wondered. I couldn't get in to see a doctor for about 3 days, and finally one of the ENT doctors I have looked at it and said "You have a stone from a stopped-up saliva gland." He proceeded to squeeze it like you would a pimple (eeeeeeeek), and finally used something like a blackhead remover thingy to get a white hard thing out of it. It stayed red and was sore for several days. Anyway, I guess anything strange we do need to have checked. I had another spot on the top of my tongue that looked reddish come up a few days ago. I was scheduled for a dental appointment anyway, so I showed it to the dentist. He didn't know what it was but said it didn't look like anything to worry about - said most tongue cancers usually come up on the sides or under the tongue. I went to an ENT doctor and he looked at it and felt around saying it wasn't hard or anything and to just watch it. He prescribed nystatin to rinse in my mouth. That was about 4 days ago, and I think it's better, or at least not so red. I may go to the other ENT doctor next week if it's still there. Anyway, if yours doesn't go away, like you said, in 72 hours, go have it checked. It could be a mouth ulcer - I've had them before on the inside of my lips.
julieann