Sorry about that.....here are some studying tips that may help you for next exams:
1-Study at 45 minutes intervals with 15 minutes break in between. The brain has a limit in how much time it can stay focussed in a repetitive task.
2-Sleep well. All nighters are actually really inneficient for studying purposes. If the brain lacks the sleeping time it needs, it will not perform at 100% capacity.
3-Get rid of all distractions during your study time. You want the time spent to be efficient.
Wish you the best and hang in there.