White smoke out of exhuast?

i have a 3000gt and its driving fine just like it always have been, and i just pulled into a parkin and had to move so i restarted the car and it was ruff like Fuel presser problems but it did start and then white smoke came pouring out more and more then i reved it and more. but then i drove it and it went away. drove it next day fine as i was drving i noticed smoked again. it dosnt smell like anti freeze, its white as hell. but the car drives fine. one day i lost alot of anti freeze but it was way b4 this problem. now i do notice a slight fluctuation in the level. but not realy loosing any specialy with the amont of smoke comming out what elce can cause white smoke. the car drives fine like it did be b4. no change in drving style. what could this be what should i do to get a little more life if it is the head gasket. i just want a couple of more months if i can but can drive with a smoke screen.