Just pay attention to it. If it goes away once it gets a little warmer, then it was just the temperature. 50 is around where it while smoke a little until it warms up a touch. It's still worth pressure testing the cooling system just to be sure. Not an expensive procedure, or you can buy the tool yourself to check it.
You simply pressure the system up with the tool, and if the pressure drops (I can't remember what an acceptable drop is in what amount of time, it'll be in the manual with the tool), then there is a problem.
You can also have someone fire up your car for you, and smell the exhaust. If it smells sweet, that's coolant burning.
Don't inhale too deeply though, or you'll get high and random passerby will be able to take advantage of you. lol
Keep an eye on your coolant level as well.