Unidentified bite?

About a week ago, I noticed two bumps on the underside of my forearm. I'm really prone to rashes and hives so I kind of ignored it. But, a couple days ago, I noticed that there were puncture marks in the center of the bumps, about 1 mm wide. One bite was bigger than the other and there was a small ring of redness and swelling (2-3 mm) around each. They were maybe 5 mm apart.

I've been keeping an eye on it since then and the wounds have closed up and swelling has gone down a little. There's a slight burning sensation sometimes and it's always kind of itchy. I'm not too worried, but some of what I have seen on the intarwebs (oh god brown recluse) gives me nightmares.

I live in a suburban area of Phoenix, AZ and I'm not outside that often. I'm thinking I might have gotten bit while sleeping.

Any ideas on what it is or good ways to treat it? Tweet