hi, i had my last periods on 27/01/2013. Had protected intercourse on 2/02/2013. The condom did not break and no ejaculation took place. Now i am 11 days late. Have taken many pregnancy tests. The last being yesterday. All are negative. No other symptoms. Got an ultrasound, endometrium is thick but no g-sac and everything is fine. My doctor said i should wait for my periods but i am really nervous. What else can i do to confirm i am not pregnant? Please help.