i have not had a period in 5 months. taken many pregnancy test they all said neg. so i went to doctor and he does an exam and says come back in 2 wks. He also said when i come back they will do a pregnancy test. He also said no sex during 2wks.why? and why could he not tell if i was pregnant? what could be wrong with me? my stomach has started getting bigger and i wonder if i am pregnant.