had to jump start my car last night after the movies since the car would not turn over. thought the alarm went off and drained it but went to the hardware store this morning and it happened again. after going home a hooked a car charger to it till it read 100% charged. after first crank and turning it off after 1 min. the battery was at 70% and 60% after i tried a second time. engine would not turn over. does anyone know if its a alternator problem or battery?