I'm not sure if it's true of all universities, but at mine if you submit late (within a week after the deadline) you will get your assignment marked but it will be capped at a maximum mark of 40% - it may be worth checking (if you haven't already) if your university offers this? After all 40% is better than a 0 if you can get it!
Alternatively send some e-mails to lecturers and explain how you are feeling, in my experience lecturers are just as much human as we are and may be understanding to your situation and offer an extension of some kind - worth a try!
I would say as well to start attending lectures from now, honestly the best advice on assignments you will get are in these sessions. From experience, as someone that attended little to no lectures in first year (finished with a bare pass), to having full attendance in second year (finished with a first), lecturers are a lot more keen to help in situations like these if you have some kind of relationship with them and they know who you are - good luck, I understand it is hard but don't be afraid to ask people for help, everyone has rough patches in uni!