My brain is lying to me

I've had a very long day today and only got 3 hours of sleep. Woke up every hour. Now I'm supposed to be deep asleep but here I am wide awake. I know I should especially, especially since another long day awaits me tomorrow but I'm unable to fall asleep, I'm a little afraid of sleeping (afraid I'd sleep too much) AND my brain is lying to me telling me to stay up as long as I need because tomorrow I can sleep in and get all the rest I need, which is a big fat lie. Why is this happening ?