So many questions!

I already posted once today but I need advice. My husband tells me to relax but I can't. Nothing seems to add up - I had a faint pregnancy line on Dec 3 and then a BFP on Dec 6. Today we went for an ultrasound and they say I'm measuring around 5 weeks and there is no fetal pole but the gestational sac and yolk sac look great. I go back Jan 4 for an ultrasound but since we already lost a baby in sept due to chromosomal abnormalities I just can't calm down.