How Can A Cat Scratch Wound Be Treated?

I was bit and scratched by a stray cat about four weeks ago. It swelled, bruised and hurt a lot. I went to urgent care, got a tetnus shot and took a complete series of antibiotics. Most of the swelling went down in about ten days, but my hand ached from my wrist to my fingers after that. Now, there is a lump that is red and itches and sometimes hurts. It looks like a boil, I think. It seems to have a blister on top. Sometimes my whole hand itches. It s rather unsightly, like an infection. Should I be worried?