hi, it has been 4 months since my marriage,but unfortyunately i m not able to intercourse with my partner till now. we have been trying but after the foreplay my penis is loosing erection,when I try to insert.we consulted a sexologist and tried megalis tablet,erection is ok,but as a side-effect,i m having headache.before marriage, I have not masturbated myself.i want to know why my penis erection is lost after foreplay? please help me to find a better solution .