Pregnant?

I lost my baby at 5 weeks 1 day. This was almost 8 weeks ago. For the last couple weeks I've been experiencing lightheadedness, tender breasts and nipples, itchy breasts. I've had some light nausea and can't seem to eat as much. Also, my bf smokes and I can't take the smell anymore. It's 8 weeks since I lost the pregnancy and I'm still getting strong positives on pregnancy tests. Could I have gotten pregnant again that fast?! Can't get a doctors appointment for a little while so just worried