Hi ladies.

I need your opinions. So I had sex when glow said it was my fertile window which was just over 2 weeks ago. About a week after that I had light spotting which lasted a few hours and now my period was supposed to start 3 days ago and all ive had today is very very light brownish colour blood. I think it's too late for implantation but could I be pregnant? I tested a few days ago and it was negative. Help! I've never had this before! X