Title says it all - exams suck.

Currently taking my mock exams and they have made me tired as heck. I still have another week left of 'em, and with the new English and Maths specifications that we have in the UK the exams are extra hard. I've done some revision, but most of the time it just doesn't sink in anyway.

Only things I've been enjoying recently are BioShock infinite and World of Tanks. Literally all I've been playing in my spare time.

Any advice on how to not be so tired? I don't go to sleep late either.