Hello GalaxyDalmation, first up, welcome, and I also want to say 'you are worth more than your grades', it's a difficult transition moving from school to uni, because at school you have your friends around to support each other, plus it's a busy life, there's so much you have to learn before the exams, but once you move to uni, your lifestyle changes dramatically.
The course at uni may not be the one you wanted to be enrolled in and you have new people to become accustomed to and you have much more time to yourself, so that's an enormous change from what you had before.
If you're not happy being at uni, then postpone your course and I know it's almost the end of the year, that doesn't matter you can take it up later on if you decide, you need to get your mind sorted out with the help starting with your doctor.
Find a part time job something you would like to do something that excites you and that is possibly something that instantly changes your outlook, however, please ask your doctor about the 'mental health plan', this entitles you to 10 Medicare paid sessions per year.
Would really like to hear back from you.