Thank you so much for your answer! Yes, I was about 5 days before the expected period date. I am particularly worried because of the pink-brown discharge, because I've read that it might be implantation bleeding. It could also be some type of cystitis. But I'm not sure that could delay my period. I'm still waiting for my period to come. I hope that I won't have to go to the doctor. Thanks again!
i dont think you could be pregnant from precum if you've actually not had intercourse! You said you are 4-5 days late, and you had been with your boyfriend 10 days ago, which means, about 5 days before your expected period date?
It is tough to get pregnant that late in your cycle.. so it looks like your period is late and these could be symptoms of PMS.
You could do a hpt test if you are already late for your period.
Going on birth control pills, and mental stress may also alter your cycle.. good luck!