How To Treat A Sore Clogged Sweat Gland In My Armpit?

I've been working out intensely, and I had this happen a few years ago (I think in the same spot), but I don't remember what the Doc did. I have a clogged sweat gland in my armpit. Right now it is a small bump, but it is sore and bothersome. Can I treat this myself?