I noticed you have an MSI board. It seems typical that the MSI boards read a little higher than the others. A little more time may tell as they populate through the forums. My temps on a Cooler Master Hyper TX2 with a 2500k at stock are 41c-43c at idle. I reseated my heatsink twice and checked the pattern of the ceramique and all looks good. I honestly don't think there is an issue with mine, or even yours. It could be a faulty mainboard sensor or bios flaw within MSI. If you are really concerned, hit a infrared thermometer on the backside.
If your heatsink it moving around too much, it sometimes means you are applying too much compound which in turn is making it swim around in goop and holding heat in.