Scared and nervous

So, I've posted a few times about what I'm going through but I'll do a recap so everyone can give the most accurate advice, 2 weeks ago I had 4 positive HPTs and 2 negative, as well as 2 negative blood tests. I've been spotting for over a week but no sign of AF I'm not even cramping anymore. Last night my husband and I had sex for the first time in a month and afterwards I started bleeding, I had a large blood clot come out and after that the bleeding stopped and I haven't experienced anymore. What could this possibly mean? Some say chemical pregnancy, but I should start my period for that not just minimal spotting correct?