please help so I don't have to cut my leg off

I need help now that my insurance is going up. I need to know if I need to see a doctor absolutely or if they'll just give me neosporin and go home. The first pic is three days ago and the bottom two pics are now. I've tried Benadryl, aspirin, neosporin, anti-itch cream, and multiple lotions. It's itchy and gets dry and when t first appears the "bite(?)" is hard. I know it's not bed bugs or fleas. Everything else is off bets.