2weeks delayed period, CM with tint of blood?HPTs negative..

Hi, I am 23yo and my have been delayed more than 2weeks. My AF is irregular. But these few months have been quite regular around 27-31 days cycle. 

Have had unprotected sex last Oct and my last period start on 27 oct. I have been having EWCM before and after time of due period. Just yesterday and day before I notice blobs of CM with blood streaks (sorry if TMI) and some when I wipe. But no AF yet.

I took HPT on the 1st and 2nd week delay and both came negative. IDK. Maybe it is because of being stress lately the AF is late. But can't really ruled out that I might be pregnant.

No obvious pregnancy symptoms just frequent need to pee at night especially, mild pain in left lower abdomen that come and go, uterus area is a bit hard ( I think) and thats it. 

I cannot stop thinking abt the possiblity of pregnant unless my AF show already.:-)

Anyone? Thanks!