Please help!!!!!!

My AF was due yesterday, Sunday. I have had slight cramps but nothing compared to normal..... on Friday I had pinkish light when I went to the loo and then brown string almost in the <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">eve</a> and then nothing! No AF or symptoms. I did a test yesterday and it was BFN. Still no sign of af or anymore pink/brown stuff and I don’t want to keep wasting tests.... what do u guys think?