Oops! It just occured to me that I mistyped the hormone! it is hcg *human chorionic gonadotropin* Sorry!!~
I would go see your doctor. Especially if your periods are normally regular. It also might depend on the hpt you are using. some are better at detecting it than others. also try taking one first thing in the morning, like wake up and pee on the stick. Morning urine will contain higher levels of the hgc hormone that gives you a positive test. Hope this helps!!~