It's impossible to say. The only thing you can do is take a pregnancy test with first morning urine and/or see a doctor. You could have a UTI, you could be pregnant, you could have an STD, it could be cysts...the possibilities are too high to narrow it down without testing.
But now it's not even spotting , it's going to my underwear now , and my pee is cloudy. What's happening?
Many things can cause spotting between periods. You can take a home pregnancy test 14 days after intercourse and expect an accurate result.
I strong encourage you to use condoms in the future. Condoms not only help prevent unplanned pregnancies, they help protect you against sexually transmitted infections, which your partner can have and pass along to you without even being aware.