TTC need help!!!

So I was wondering if anyone could help me figure out why my breast feel sore to the touch and feel heavy like I'm caring bricks around? Also bout two weeks ago I woke up to light bleeding pinkish didn't last but a day and the next day it was just clear discharge wit spots of dark brown blood. I also been irritated, can't stop yawning and I been super thirsty. Plus other symptoms. I took a cheap pregnancy test yesterday 8 days before my period is due and it came back negative I guessed wat I'm asking is if there could be anyway I could be pregnant?.