I had 3 cysts injected at once, and yes, right after I got them, there was some swelling. I had one on my left cheek, one on my right, and one just below the cyst on the left cheek. I felt kinda stupid walking out of the office with 3 circular band-aids on my face but now it just seems kinda funny. Anyway, my derm told me to massage the cysts a little throughout the day so that the medication would seep deeper to kill the cyst. By the next morning they were flat as a pancake.
For me, it hurt like crazy but I'm such a wimp when it comes to things like that. I do hope you'll take these injections into consideration if you don't mind a slight scar. A little pain and a slight scar are a million times better than having a cyst that doesn't seem like it's ever going to go away.