It can be too late, what decides this is if you dead on put your head down and do the work, dont overload yourself, do 20 or 30 minute bursts of going over a certain topic, taking a 5 or 10 minute cool down period, then reviewing the material. This way you can get at least some efficient work done. You should have started earlier but well, now is now and what you do will determine if you pass or not. Good luck