No period...two days late and negative tests

Colleen
I was due two days ago for period. I am like clock work. I always know when I'm going to get it. I have no cramping. Every test I've taken says negative. Does anyone think I could be preggo but test isn't showing or just that period is coming late. I'm also breastfeeding my 11 month old still if that makes a difference? Thanks for your help. I love this app