Should I trust my equipment

[Rock51]

I have a rack with heat tape and a helix. I have the helix set to 94 so I'm getting 89-90 degree hot spot and 83 degree ambient temp( using what I think is a cheap digital thermometer) . My problem is that I dropped my temp gun (ryobi brand new paid $30) and now it seems like it is giving me weird Temps that are higher than before.i though maybe my snakes would tell me what was going on but when I look 1/2 are on the hot spot and 1/2 on the cool side. Some like to switch throughout they day.

Should I trust my helix? Trash the temp gun? What thermometer should I have to verify ambient temps?

The temp gun acting weird makes me wonder if the numbers that I keep reading are actually close to the real temp...

[KMG]

If the temp gun agreed with the tstat before you dropped and now it doesn't after you dropped it I would say its the gun. Check the temp at the tstat probe and see what the two tell you.