Another period in less than 2weeks?

I got my period August 29th, we had sex that day. We had sex again September 8th. It’s now September 10th and I’m having light bleeding/cramping. I’m nauseous, my boobs are really sore. Sore boobs never really went away from before my period just wasn’t as bad. It’s achey bad again now. I thought maybe ovulation spotting but I never have it and app says it’s 2days until ovulation. My period was 5days late last month.

Tested August 29th before I started spotting, it was negative. It also wasn’t in the morning.

Could I be getting my period again? Should I test again? Could it ovulation?