Car won't start

My car suddenly did not start and could not turn over (I just drove it that morning). I could get the radio to turn on but the headlights would dim and the internal lights would not turn on. I tried jumpstarting it but it still would not turn over after letting the battery charge for 20 minutes or so. I could now get the headlights and battery to come on at the same time. The battery is only a couple of years old and the battery was checked at the last oil change (~3 months ago). It is a 98 Mazda Protege. Any ideas of what the issue could be?