if you got the coolant topped off and you can see its dropped after running it for a while then its eating it for sure. so id let it idle away for a while see if the smoke is still coming or if its just good old cold exhaust smoke due to winter temps. it will do that till the whole exhaust is good and hot.
while you let it run and idle. leave the rad cap off, rev the engine up a few times while watching the inside of the radiator. if you see bubbles coming up in the rad the head gasket is leaking for sure, thats exhaust gasses finding its way out the coolant system.
