Your energy, your focus, and your attention are your greatest resources. They're what you use to make a difference in the world; they're the best gifts you can give to your friends and family. Protect them as best you can by taking the time you need to recharge.
If from time to time you can't, be gentle with yourself and take even better care than you usually do. A little self-kindness can go a long way in making a bad situation better.
SOURCE: https://tinybuddha.com/blog/how-to-deal-with-exhaustion-10-tips-to-function-better-when-youre-tired/