I Accidentally Stabbed My Lower Gum With My Toothbrush On

I accidentally stabbed my lower gum with my toothbrush on Thursday. It has been very sore the last few days and today it has been unbearable. I didn't think I cut it but there seems to be a white pocket forming and my bottom lip and chin are now hot to the touch. Did I mention the pain is unbearable? What should I do?