I just replaced my battery with an 800 cc interstate battery 4 days ago because my truck wouldn't start and I figured it was the battery, since it was the original. The truck ran fine for the first 2 days, but the 3rd day it took me a few tries to start it and then today my truck wouldn't start. We jumped it and it immediately started I drove it for about an hour and then when I shut it off. All the electrical was dead. I couldn't even turn my lights on. Is this a bad alternator or do I potentially have some other electrical problem?