Help! Brown spotting lasting two weeks

Hello,

So just around my ovulation I started brown spotting. I thought everything was fine, because I’ve had that a couple times in my life before. BUT... it hasnt stopped. My period should start very soon, but ever since I have been spotting so I don’t even know if I am gonna get it. What could this be? K am seriously worried!!!

A couple factors, that could be relevant or not:

- this spotting started after I started having sex with a new partner after a long dry spell (PROTECTED sex - with condom)

- I am currently on my 25/30 days Doxycycline antibiotics for acne.

- I am not taking any kind of hormone pill.

- I am 21 and not trying to get pregnant.