Does Brown Vaginal Discharge, Constipation And Tenderness In Breasts Indicate Pregnancy?

I was due for my period yesterday. Instead I had clear sticky discharge with a tinge of pink. Today I have really dark brown discharge. Not a lot. And still no period. Had lots of cramps and now diarrhea. But still doesnt feel like I m going to get my period. My breasts are tender, and I have been bloated and constipated leading up to today. Took a test today and the line showed up then disappeared. Could I be pregnant?