Half your worst moods are just you skipping lunch. Know the difference between hungry and hurt.

Physical state gets mistaken for emotional state constantly. Hunger, poor sleep and dehydration all produce something that feels exactly like a bleak view of your life, and the mind obligingly supplies reasons for it. The feeling is genuine. The explanation attached to it is frequently invented after the fact.

Run the simple checks before you trust a sudden mood. Have you eaten, did you sleep, when did you last go outside. Deal with those first and see what remains, because whatever survives that test is the thing actually worth thinking about.