I haven't done anything this holidays...but that's probably cuz I've got a fever
Your not the only one. I've had my break to wake up this morning that I'm going to start work, chocked up, fever, exhausted and unable to think 
well i've had my fever since Sunday and I haven't been able to do any study :/
I feel so behind!
It's been going around for ages, that. I was bedridden for a few days early last month... I was only awake twice a day for about three hours at a time, and doing a task even as simple as putting clothes in the washing machine physically exhausted me. The only bright side to it all was that the constant fever meant I was burning heaps of calories... I lost about 3kg even though all I did was eat, drink water and sleep, lol.
Make sure you keep your fluids up, and take the time to get better!!
It's not going to do you any good in the long run if you push yourself too hard now.