battery being drained?

I had a bad head light in which the low beam filamet was broken but the high beam worked fine. Could this cause so kind of drain on the battery when I used the head lights? My battery, not even 2 years old is dead and once I replaced the battery the car seems to be working, but it could be the alternator, even though the alternator is also less than 2 years old. Any help is appreciated.

not really likely, the drain is probably something else

i dont think so. but i don't buy batteries anymore, i got a battery charger:)