Anger often acts as a pressure gauge for stress you’ve been carrying too long....

https://www.web-bookmarks.win/anger-is-rarely-just-about-being-mad-it-is-usually-the-result-of-long-term

Anger often acts as a pressure gauge for stress you’ve been carrying too long. You might notice it in a tight jaw or shoulders that never quite relax, or perhaps in the way your sleep suffers