The other night i was masturbating and i think i jerked a little too hard. Ill try to be as specific with this as i can be. Right below the tip of my penis on the underside, there is a small red vertical line in the middle of the shaft. It now hurts to masturbate unless i use lotion and its swelled more than ive ever seen before. Idk if i pulled a tendon or something but i want to know if i should see a doctor.