You need a drink
Forget about everyone else and take a break. Go to your favorite bar, coffee shop, or restaurant. Ask for the table of 1 by the window, or sit in that corner booth. Have no purpose but to sit by yourself with either a newspaper, novel, or some earbuds with your favorite music. Keep the computer with the work proposal due in 2 days in the car. Just relax with a cup of coffee, iced tea, or my drink of choice, champagne. Surround yourself with a beautiful atmosphere like a hotel lobby lounge and just relax, checking every thought, good or bad, at the door.