Ant Bite?

Hello,
Something bit my big toe yesterday morning...I felt the little bite, it felt like a pinch. It felt similar to a fire ant bite, so that's what I thought it was. Last night the little white head appeared and my toe swelled up a little bit. This morning I noticed that the white spot turned into a dark reddish blood blister. The swelling has gone further up my toe and is now not in the next two toes, but above them. I've never had an ant bite like this! It's not really itchy, just uncomfortable because of the swelling. I've been putting cortisone on it. Any ideas as to what took a bite out of me?