??????

I am pretty late on my period and we are actively trying to conceive and this morning when I went to the bathroom about 9 am I noticed a little bit of blood mixed with clear discharge so I thought it was my period so I put a tampon in and go on about my day...come like 12:30 pm I have the finest bit of blood on my tampon. I’ve been taking lots of pregnancy tests from the 99 cent store and they have all been negative??? (Sorry about the pee lol)