My Sensors In My Left Leg Is Different. It Feels

my sensors in my left leg is different. it feels nothing even if i pinch it. due to that, it became my mannerism to pinch and pinch my leg until it resulted to a wound. When my wound gets dry, i peel out the black cover making the wound fresh again. ihave had checkup up from my doctor and he said my sensors in my left leg are not working well. he gave me antibiotic but i became allergic to that medicine, so for now, im only using Chlorhexidine digluconate, an antiseptic wound spray which my doctor gave me. this time, a boil with water inside suddenly showed in my leg beside my wounds. i accidentally made the water out from that boil. then this boil after one or two days, contained a pus and im really alarmed because that part is now a large area with hard muscles i think. the pus is still not removed. What should i do? Idont want to go back to my doctor because the checkup is so expensive and the medicines he give is also unaffordable.