Rep Power: 0

I just changed out my battery and alternator on my 2004 honda civic lx 3 weeks ago. Everything was going fine until I was driving to work one morning and hit a big dip in the road pretty hard. I got to work 5 minutes later. The next morning when I got in my car to drive home my battery light was on. I work an hour and a half away from home so I didn't stop because I didn't want to be stranded. I barely got home and turned my car off the tried restarting it again. It didn't start. I took the battery in to get tested and they said it was dead so they warrantied me another one. Then I went and got the alternator tested and they said it was a bad alternator (not producing the power it should be) and to take it out and they will give me another one. My question is if it was a bad alternator how could it last 3 weeks with no problems then poop out. Wouldn't it happen right away? I'm afraid when I hit that big dip I might have loosened or damaged something causing the alternator to not function properly. Is that possible. Any advice would be greatly appreciated. Thank you.

 
Rep Power: 812

its possible something came loose. either the alternator wing nut (which would cause loss of belt tension) or maybe the power wire if it wasnt tightened enough. also could be loose connections at the battery. but i have had new alternators die in a few weeks or a few months before (not on the civic). it could also have been a bad battery which caused the alternator to have to work too hard and burn itself out. ive seen that happen too.