Hi Sir.. I Was Having Problem Of Irregular Periods And

Hi sir.. I was having problem of irregular periods and after taking course of ovral g for 21 days, my periods were ok. But in the month of August I had a foreplay with my boy friend (not sex) and from last 2 months I am not getting my periods. I also took pregnancy test (prega news) and it was negative. I am absolutely sure that I didn't had sex. I am virgin. Please guide what should I do asap..