Too early to test?

Hayley
Last Tuesday I had implantation bleeding or what I thought was implantation bleeding. It was super light brown and not very much. Anyways it is now sunday. 5 days later. I took a frer test this morning when I woke up. It was negative. Is there any way it was just too early to tell? With my son I didn't get a positive until I was 2 weeks late. My period is supposed to start on Tuesday (in 2 days) according to my ovia app. But that app is wrong about when my period is supposed to start and usually glow is right. According to glow I should have already started last thursday.