I'm guessing that you're an introvert and being around everyone in the office is what wears you out. If this is case, try and move your desk to a quieter less crowded part of the office and invest in some good headphones. You can also try going out for a walk in the middle of the day to get away from everyone.
Another thing you can do is focus on having more energy by doing things like working out, eating better, etc. If you are always tired you might want to go see your doctor and check for hypothyroid and / or low testosterone (assuming you are a middle-aged man)
Another thing you can do is focus on having more energy by doing things like working out, eating better, etc. If you are always tired you might want to go see your doctor and check for hypothyroid and / or low testosterone (assuming you are a middle-aged man)