Good for you for being safety-minded. The color, as brenndatomu mentioned, is likely throwing off the reading. Can you hold your hand against the wall?
Don't leave this there, but do you have a piece of black construction paper that you could temporarily tape in the spot of concern, leave it for ten minutes, test the temperature, and then remove it?
I've read in other threads on here that 90 degrees above the ambient temperature is okay, but I'm no expert. In fact, I'm rather cautious, and I think 150 degrees would make me nervous if that's an accurate reading.
@begreen, do you have some sage advice here?
Edited to add: The other day I think that my youngest adjusted the emissivity on our infrared thermometer. I asked my husband to measure the temperature of something, and the result seemed off. When I questioned whether it could be right, he checked the palm of his hand and got 160 degrees. I adjusted the emissivity back to a more standard setting and immediately got more credible readings.
Infrared thermometers are great tools but don't panic over your first reading until you do more investigating.