Off of Depo

Hailey
So I got my first depo shot back in October and once the 3 months was up I didn't take it again because I've gained a lot of weight and I spotted the last 2 months of it and a month afterwards. I last spotted on Feb. 3 and I haven't had a period yet but my boobs are sore and I've been cramping a little and had a bit of brown spotting/ discharge once last week and once this week. When will I get my period again? Is this normal? Are my boobs supposed to be this sore?