Didn't get my last depo-provera shot 2 months ago and i started prenatials almost 5 months ago and i'm having 2 periods a month. normal?

No: Having more than one cycle a month isn't normal. Sometimes when getting off of Progesterone based birth control like the depot, a woman's periods can be irregular. I would give it another 2 months. Other causes could be extremes of weight (thin or heavy), thyroid. If not better in a month or so, see a doctor for evaluation.

Expected: Depoprovera takes a long time to get out of your system. For some it can take up to a year. Cycles will be irregular until it is out of your system.