Forgot to deregister with the authorities (CPR) (Copenhagen)

I studied at the University of Copenhagen from last September until January this year. However, I forgot to deregister with the authorities. Does anyone have any suggestions of what I should do? I am really scared that I am going to have to go to court in Denmark or pay a really big fine which I will not be able to afford as I am only a student. I am going to Copenhagen next month and I was thinking I should deregister then? Will I have a penalty of some kind?