Nissan Repair Questions? Ask a Mechanic for Answers ASAP
What you describe certainly sounds like a bad battery. As the battery dies it will be less and less able to provide enough amperage to start the car. This means that it will sometimes still be able to run accessories, like headlights, radio, etc, but won't have enough amperage to start the car. Normally as you drive the battery would charge back up, but if the battery is bad it won't charge like it should and you will have to jump it again and again until you replace it.
I wouldn't think so. You might have the alternator tested to make sure it's charging correctly when you have the battery changed, but we don't see them go out very often on the sentra.