I'm a bit confused please help

Emily.
I started my period when I was 14, that is also when I got pregnant. After I had my baby I never got AF again and when she was 9 mo I got pregnant again. I stopped breastfeeding my youngest about 4 months ago.. My period came back and has been on time! Except I haven't had my visitor since June 19th. I have taken pregnancy tests and there all BFN so idk why my period isn't here!! Any thoughts? I would go to the doctors but my insurance isn't covering me right now.