Tired, Angry, and Stalling
The two times when you must be especially careful are when you are tired or angry. Combine them and regret is almost certain.
If you have all of the resources for a decision or action but are lacking the proper frame of mind, then it is wise to buy some time, even if it is for as little as 30 minutes. I've seen people who damaged their careers for years because of one injudicious remark or decision made at a moment when judgment was obscured by fatigue or emotion.
Alarm bells should sound whenever someone claims that a decision must be made immediately. Such deadlines are rarely real and the person who is pressing for a commitment is using one of the oldest power ploys in the book. Let me make a suggestion that is only slightly tongue-in-cheek:
Ask "What would Calvin Coolidge do?"