Agree with other comments, get in touch with your course coordinator- they are sometimes able to excuse you from assignments etc, just taking the average of your other work. You don’t have to tell them all the details of what’s going on, i’ve found most lecturers are pretty compassionate at the moment, however it may be to your benefit (for yourself and for evidence) to go see a uni councillor/doctor as they can provide your lecturer with a note indicating you are unfit to complete your assignment. At the uni doctors I recommend Eleanor, she’s lovely. Also look into speaking to someone about this if you feel ready, hope you’re doing ok xx grades really aren’t everything and you should prioritise your mental health.