Some places drain you of your energy. Some people drain you of your energy. You could be completely drained and fatigued because of seeing a number of these people during the day. You think it's from lack of sleep. Then, evening comes and all it took was seeing one person and you are completely energized. How do you explain that? Shouldn't you be more tired after a long day if it was just simply lack of sleep?
BE COGNIZANT OF THE ENERGY (OR DRAINAGE OF ENERGY) BROUGHT BY PEOPLE AND PLACES. MORE IMPORTANTLY, BE AWARE OF THE ENERGY YOU BRING.
Here's a simple writing exercise for you to do in your journal daily (or however frequently you want to do this.) Write down and describe the places to which you've been today. Describe your energy level. Write down the people you came across today and describe your energy while you were in the same proximity of these people.