after i ejaculate, the tip of my penis turns red and becomes uncomfortable. it doesnt hurt or itch but is just uncomfortable. i have recieved oral sex from several girls over the past several months but have only had vaginal sex with one girl and i used a condom. i haven't seen any other posts that matched my symptoms exactly and am not sure what is wrong. i recently started dating agirl and before we get intimate, i want to make sure that i dont have anything to give to her. could this be an STD?