Does anyone still have a negative amount of money on their student account? Is this a glitch or does the school actually owe me money?

the school owes you money, perhaps from cancelled courses. You can go to student accounts/cashiers and ask them to send you a check to your address to claim it.

can i pick it up too? Or do they have to mail it?

I don't think you can pick it up in cash, it's usually cheque that gets mailed to your home address. Wont hurt to ask though!