Can they feel pressure changes?

theres a storm over here in illinois and im wondering if pressure changes cause different behaviors in scorps

Im not an expert, but I think they can tell when the weather turns foul (IE: Rainy, stormy, etc.).
The reason I think this is because my Emperor scorpion, Knuckles, usually rests and hide out during the day, but yesterday when it was raining all day long he was really really active almost the whole day and even a little into the night.
So Im gonna go with yes.

mine did the exact opposite, he had his claws out, and when i opened window in the hall, he hid, and hasn't come out

Did he have direct light shine on him from the window? Or perhaps a breeze?

he has light on him all day as my family was more supportive of breeding crayfish than scorpions, and are trying to make it as hard as possible, so i use a fish light that gets it up to 80, but the thermometer broke about 3 weeks in, and i cant get another heat source and if it breaks im screwed bcuz being next to windows in illinois winters = not good

the window had been open in the hall most of the day, and he didnt come out at all last night as far as i could tell

Thats unfortunate about your family being unsupportive. But As far as the lights go, you have an IR bulb right? Because if its anything other then a IR (infrared) bulb then it will stress em out. Thats why they like dark places. Its also been my personal experiance that they dont like breezes very well. Pretty sure that stresses em out to.

On a side note, I know what you mean about winters. I used to live in Montana (very cold) and now I live in North Dakota (extremely cold), so its not good either.

It says Eclipse Natural Daylight, and its a bar sort of light, like the long pvc like ones, other than that nothing.

Yeah definatley only use the red infrared bulbs. Go to pet smart or something similar. They can set you up.