am I pregnant or not?

I have a little babyboy his 1 years old and 7 months on agust 11, 2016 I had got my depo shot and I had to go back to the doctors on November 11,2016 and I didn't go.... on January 11,2017 I had sex with my hubby a week ago I started to get back pain my lower stomach herts and my boobs were itchy but it went away I get dizzy and naueos it goes and it comes but the pack pain and the lower stomach pain stays when I see yellow I also see a discharge but it's been since October i haven't go my period can anyone explain to me I'm worried 😔😔😔