Why did my microwave just blow out on me?

United States
September 24, 2010 4:42pm CST
I just went to heat up some coffee and my microwave started to smoke and make loud noise. This was not the first time I heated up a liquid in the microwave. I had it just over a year could it just be time to buy a new one? My sister bought me that for Christmas and a housewarming gift. I am so mad now being I was taking it to my new place next week.