Whenever I get back on my project, some variables are not what I set them to and some sprites are in the wrong layer (It's always the same sprites and variables). Also, I made some code that worked perfectly well and then decided to get off, but when I came back on it stopped working, and  didn't touch it all.  Is Gandi IDE just glitching?

are some variables marked "this sprite only"?

yes, but not the ones glitching out. I am able to fix it, I just have to reset it every now in and then

I never encounter this bug before. It might be a problem with your code, like do you remember to reset the variable after use?