thank you for your query.
You are most probably suffering from the side effects of the Depo shot.
It is common after the Depo shot to have irregular periods
for a few months.
Also, breast tenderness is very common.
Obviously, you would not be feeling baby movements this early, as fetal movements are felt only after the fifth month of pregnancy
Please consult your gynecologist for knowing the exact cause of irregular periods and also to check for pregnancy, though it is highly unikely.
Give yourself some time to come of the Depo, and if not planning further kids, use condoms meanwhile.