I have been using this a now for about 6 months. According to the app my periods are very irregular. Once every few weeks. The app is now telling me that I am 21 days late for my period and should be starting a new one here in a few days. My question here is

When we ladies have other lady friends we hang around a lot and then we suddenly stop hanging around them, does that mess with our bodies, just like when they try to sync up?? I don't think I am pregnant, no signs of pregnancy and 4 home tests all say negative. I've been to a doctor as well and that test also said not pregnant.

I've never experienced anything like this before so any advice would be greatly appreciated.

Update: I just started my period, 34 days late but I I am excited that I have started. I have never been so happy to start bleeding. Thank you for all of your help ladies.