So according to this app I am late 27 days.

I am still breastfeeding my 21 month old, my period was already pretty regular for about 6 months. Is it possible for my period to go away because I am still nursing him?

My husband had a vasectomy last year, and I'm getting negative pregnancy tests which I am relieved about but freaking out about my period not coming. I have never skipped a period before

Any advice?