Sting or Bite?

Interesting thing happened to me at work today. Two hours into my shift my left ring finger became itchy, and then it got really hot... so much that running it under cold water wasn't helping. All my other fingers were fine, and I felt fine apart from that. Not long after my finger swelled up quite a bit and was suffering in pain. I didn't know what to do... and after talking to my friend over what I should do, I told my supervisor who gave me an icepack to carry around. My huge finger could not feel the cold from the icepack, although my other finger froze. Oddly it wasn't the whole finger that was suffering, just the middle part - which made it really painful to try to bend. I'm not sure if it was a sting or a bite. Just before I left work I noticed the swelling had gone down and now it feels almost back to normal. The strange thing is that I didn't do anything out of the ordinary today... so I don't understand how this could have happened.