Weird wound on my leg, possibly a burn and cut.?

i was riding my old ass mongoose bike and i have no brakes so i stopped with my leg on the back tire and i somehow put my left calf on the tread and it was painful. when i got home, i noticed it had torn all skin from my wound. i put peroxide on it and it stung badly and fizzed up. i now have ointment and a bandaid on it and its leaking pus as i type this. its about 2 inches tall and 1 inch wide. its sore and red with purple scabs and it protrudes from my leg.