I don't want to be "one of those" posts but I've been worrying myself sick. Pregnant?

We had sex, and the condom came off inside me. He went for just a few seconds before we noticed but he didn't ejaculate at all at that point. It got stuck all the way inside me and he had to pull it out. Is there a chance I could've gotten pregnant from this? It's only been two days. I've been nauseous and my breasts hurt and I spotted a small amount of blood earlier today. But I feel like the nausea and bleeding could be from the unhealthy amount of stress I'm in from this. And I think my breasts hurt from him during the actual sex. I've been crying all day, I'm so scared.