Dear Doctor, I am 29 years old Black Man, I recently met a women I really like, I never heard any sexual problem in my life until recently after meeting this girl, we heard a good sex for the first week, and second week, I could hardly finish the second round, because my penis just loose erection, this is the third week its getting worse because I can not even get erection, sometime I do but not strong and when I do it does not even last for over 3 minutes, I would like to know the cause of this and the solution please