I got the depo-provera shot aug 4 for the first time and i got my period yesterday. is this normal???

Yes: Regular use of Depo-Provera can cause spotting & irregular menses even as it's effective. Many women end up w/o menses after a year of shots. Remember that while Depo-Provera (and other birth control pills) will keep you from getting pregnant when used regularly, they won't prevent sexually transmitted infections. For that, you'll need to make your partner wear a condom each & every time.