Run Bitch, RUUUUUUN

HD OK been working on this for a while and when i mean a while that ive been on and off this for about 2 months. I liked how everything came out but I NEED HELP ok so the file i got this from is HD and when working on it, it was 720 or higher like i got it but everytime i rendered it, i can tell the frame rate dropped or something cuz it looks more like a indie film than how it actually looks like and i tried looking it up but didnt find anything so i was hoping one of you guys could help me with that