Disseratation dealine in 3 days


I have my dissertation submission in 3 days and I don't even know my topic. Just that I want to work on affordable housing. I haven't been to meet my mentor even once. I don't want to spend an extra semester because of this. On the scale of 1-5, how bad is my situation? Can I do this in three days? Or rather I should accept my fate and start working my things in such a manner that at least I clear my exams and be prepared to work my dissertation next semester. With my family problems and my chronic procrastination, I'm afraid even those additional 6 months won't help. Please someone guide me through this.