The normal typical body temperature is commonly acknowledged as 98.6°F (37°C). A few examinations have demonstrated that the "ordinary" body temperature can have a wide range, from 97°F (36.1°C) to 99°F (37.2°C). A temperature over 100.4°F (38°C) regularly implies you have a fever brought about by a disease or ailment.
how are things now? Are you back to normal?
So, is this a digital thermometer either in your ear or on forehead? I own a couple of these (I have kids and we have this or that to take temperatures for a few times every winter) . . . and I notice this too. I have chalked this up to literally being the device. You probably would not get a big difference. If it is an ear thermometer, it may be how far you put it in and that kind of thing. Often mine, if I take subsequent temperatures, the temp will rise. So, I go with the first one or if I consistently get a temperature over 100, call it a fever and just go from there.
Would guess this is the case for your situation. Glad you are over your cold! Did you have a fever with the cold?