corn snakes color change and acting skittish

I have a corn snake who is 34 inches long. I have had her approximately 6 weeks. I have no idea how old she is. she belonged to my nephew and I got her when he went to collage. She usually eats well but this feeding it took her a little longer to latch onto the mouse. She has been acting nervous and not moving around as much the last few days. She strikes at me when I reach into the cage and has been hiding a lot. She usually moves around and explores her viv but she hasn't been these last few days. I noticed today her coloring is different she has more yellow along her sides and her orange is darker. I got her out and checked her over and noticed her belly has these sort of lines like wrinkles on it and appears to be more silvery. She feels smooth and supple. Her eyes have been a little whitish the last few days too. She shed 4-5 weeks ago. Could she be shedding again? She has this skull hide that she likes and she has been weaving around the eye and nose sockets like she is trying to tie herself into a knot. The last time she shed, she wrapped it around a cardboard box. I never noticed any color change then. I just got up one morning and there was a shed skin wrapped around her box hide. I have been using a black light bulb for heat because I broke her night bulb I got from the pet store. Could that be causing her problems? I bought a heat mat and installed it on one third of the viv but the pet shop didn't have a thermostat for it. They told me they never use one for their snakes and it wouldn't get too hot. I noticed her laying on top of her hide and refusing to touch the floor of her viv on that side. When I checked the temp it was 100 degrees. I turned off the mat and have ordered a thermostat on line that should be here soon. Until then I went back the heat lamp. Glad I only had the mat on an hour. It would have cooked the poor thing. Could she has gotten burned? She was acting funny before I put in the heat mat though. Could she be sick?

Just sounds like she is going blu for now. They can act abit different because they cant see as well and the skin is tight.

I agree with Cat_Eyed_Lady, she is probably entering her next shed cycle. They can't see as well duing that time so they can be more nervous, even a little nippy, and they tend to hide more since they can't see a predator coming.

I'm glad you ordered a thermostat. I very nearly cooked a beautiful little rosy boa before I knew better. When I discovered the temerature he had been living at, I felt awful.

One of mine turns vicious when in blue. Sounds like what is happening to you.

More than likely, it's because she's in blue. It would be a good idea to check her over real well, in case she has burned herself on the heat mat.
I'm glad you ordered a thermostat. It can be very dangerous for them to have unregulated heat. Some people have lost animals.