I am 35 and have unprotected sex with my boyfriend frequently. My periods are VERY regular. Well I started my period as usual on Dec 31. However, it was not normal. It was light and long. Then yesterday, Jan 16, I started again. This time it is like it normally should be. My doctor said it could mean I am pregnant. Then I had a neg HPT on Jan 16, is it possible it is too early to show positive? Could this be a miscarrage or other problem?