Exercised yesterday...Had my baby 3 months ago

I have never like exercised ever before but I hate my body I want to lose this fat I have. I feel like my flab has gotten bigger. I've been on depo since December. Is that what's made my flab bigger 😳....I barely eat anymore... I done squats yesterday. I ran in place I did a couple things to help your abs or whatever. Your stomach right? I kept bringing my knees to my chest like 100x and all that I did yesterday hurt my legs so bad...I can barley move. Did I do something wrong. ? I don't know what to do to lose this fat 😢💔