Hi I am 26 yrs old.Planned to mary this yr.I have a problem on my penis.. i can do retraction of my foreskin with out erection with a little strain. But during erection it is really painful like my penis neck was tightened by a rubber band. actually i consult a Dr. They gives me an ointment to apply and ask me to do stretching exercise everyday. But sometime i cant bear the pain so that the penis cant with stand the erection. any body help me.