Callejero

I recently got back from the field , and it had been about a month since i had started my car. When i tried to turn it the battery was completely dead. After i replaced the battery the car would start and run fine. One night i was backing up from a parking space and slightly backed onto a curb. i pulled forward and the car immediately shut off. I had it towed home and put a brand new battery and new clamps again to see if that was the problem. The car comes on fine it just won't turn over. Any ideas what it could be? Im thinking either the starter selanoide or alternator? Any suggestions would be appreciated