It's a vicious cycle. The more I move, the more my body needs the rest and the things I need to do that require sitting pile up but the more I sit the more I need to move but the more I move...

It helps if I sit weirdly. Like twist my legs to weird positions and change my position often.

What I'm baffled is that how the heck all the other people in my class can sit normally through all the classes when I, at the very instant I sit down, take my shoes off, put my woolly socks on and lift my legs to the same chair I'm sitting on or I constantly move my feet because if I don't everything starts to ache because I should be moving, not sitting.

I have to remind myself to update Hivers about my studies at some point. Fortunately I still have time. Until spring 2025 when it all ends. :D

days of 14-15 and nights of 2-5 degrees

Sounds like a typical Finnish spring. Or some years also summer. Hrrrh...