Really worried

Okay so about 1 week ago I took a plan b because when I had sex the condom ripped. There was pre cum but not full cum in the condom. I got some brown discharge today and my ovulation period ends in 1 or 2 days. I'm 16 and idk if I should be worried.

** Btw I took plan b the first day of my ovulation cycle and its nearing the last days. I'm feeling little cramps, I feel dizzy and not really having an appetite. But i took it within the 24 hour period of the condom breaking. I'm seeing stuff saying that it won't work if I'm already ovulating. I'm freaking out.