Today after oil change otw to work I noticed white smoke blowing thr the exhaust. It stopped after a few mins as I made it over. It was a hot day n my thermostat seemed to have fluctuated slightly towards the center of the gauge. But now while driving back home during the night. There seems to be no problem. Is my temperature reading in the picture above normal? Is this something I shd be worried about? PS: The smoke wasn’t dense it was translucent.