My period is 8 days late, I tested and saw 2 lines, one dark and one light. I went for an ultrasound and the doctor said the endometrium is thick but the gestational sac is not visible, the fetus may be implanting. So doctor, can you tell me if my period is late, the endometrium is thick but the gestational sac is not visible, does it mean I am pregnant? Thank you doctor.