Confusion: Could I be pregnant?

I'm trying to get pregnant. I took a pregnancy test the day before my period came. Negative. I'm day 17 of cycle experiencing brown discharge. I read it could be ovulation, I took my OPK and no line. Is it possible after all this to be pregnant. I read that could be other reason. I would have had to ovulate really early or had a period (which was about 5 days early) and still be pregnant. Any suggestions for me?