Randomly swollen cheek and sore jaw?!

My left lower cheek just swelled up out of the blue. It doesn't hardly hurt except for my jaw is a little sore. This has happened before on the other side of my mouth a little after I had my wisdom teeth out. (after all the surgery swelling had gone down of course). It just randomly swelled, then after a day or two, it just got smaller then disappeared. I'm pretty sure it was some kind of drainage and went away from being punctured some how. Just wondering, how do I get rid of this new one??