Seriously confused

I am now very lost. Earlier last month, I had sex without a condom (haven’t been on birth control for years). I know when I ovulated, tested and had ovulation spotting. And then had spotting brown for a week or two after that (this happened with my first child). Once the spotting stopped, I took a few tests and they were positive. A few days before my expected period, 2 more tests were negative. My period has not come and I’m feeling nauseous but I took another test and it looked so faint that I can’t tell if it was really positive. Can someone help me figure what’s going on with me?