The injection

Hey. It's been a while since ive posted purely because I've been so lost in my menstrual cycle! I was on the 2 month shot for 8 months - gained 20kilos and then when I went off it in March I was given a month's pill just to regulate it. But I haven't had a period since March! Has anybody else experienced this? My body feels like it's about to have its period but I don't want to get my hopes up... :) any advice and wives tales would be appreciated! Definitely never using the injection again