Painful bump in back of mouth

For 5 days now I have had an increasingly painful bump on my gum, just to the left and a bit further back from where my top, right wisdom tooth used to be (I had the tooth removed 5 months ago). The bump is not hard like a bone, but it is harder than the gum around it, kind of like hard cartilage. Is this just another form of canker sore (I get those alot if I don't use mouthwash)? Is it something I should be concerned about? What do you think it is?

[Jerome Bogin, D.D.S.]

I can tell you what it might be without seeing it but it does not sound like an aphtous ulcer. I definitely think it should be looked at but I don't think it is serious.