Bad burn on my arm! Help me out, please!?!

I burned my arm with a lighter a little less than a week ago ("smiley face" burn, yeah I know, it was stupid.) and its since popped on its own but its not really healing, and its got a strange scab thats like yellow-ish, white, and I can see veins or nerves in it, not sure exactly. Its been red around the edges since the blister first came up. People have looked at it and said its either 2nd or 3rd degree burns. Its started to hurt today. Ive been putting neosporin on it constantly. What else can I do? Its worrying me. Going to the doctor is out of the question.