Suggest Medication For Large Lump On The Shaft Of Penis

hi i am 18 and i have a slightly large lumpon the shaft of me penis that is underneath the skin butvery visible. ive had bumps that i could squeeze puss out like a pimple but this one is not the same. I am not sexually active as of almost a year now and have had unprotected sex once and i masturbate on occasion...help me!!