Confused?!? Could I be pregnant?

Okay it's a weird one and I still can't get my head around anything I'm currently waiting for my doctors appointment next week but thought I could see if anyone's experiance the same and has any answers... 

For the past 3 weeks I have experiance really bad tender breasts and nipples with them beginning to look fuller aswell(I've never experiance breast pain only during my previous pregnancys), I've had some heartburn and frequent urination aswell. 

I had my period which came a few days early, I was due on the 25th/26th buy came on on the 22nd and was off by the 24th  after my period I started getting mild stomache cramps and the sore breasts frequent urination and heart burn stayed, I've also the past few days started to get more tired aswell.

I've took a few tests since the first sign of sore breasts occurred but one was invalid and two was negative 

Today I went to the toilet and as I wiped sorry if tmi but when I wiped then was a bit of pink blood on the tissue

My heads baffled has anyone experiance this could I be pregnant?