Why The Penis Hurts Whilst Erect?

My penis was recently bent too far toward my toes during intercourse, i felt a sharp pain at the time and what looked like a ligament/guitar string that was central at the bottom of my shaft moved 1cm to the left. Other than the sharp pain at the time it never hurt, now two weeks later it is hurting. I'm experiencing a dragging sensation in my stomach. There is a large vein & the ligament left of centre on my shaft, it really hurts whilst erect, it looks and feels like the vein and ligament are not the size they once were. Due to this my penis is being pulled to the left, this does not bother me, its the fact that it hurts whilst erect. I have rested since the incident & also seen my doctor, whom said its nothing to worry about. Although it is really depressing me, as i'm worried it will be like this for life. I'm a healthy 26 year old. Please help