Note: Not everyone experiences it exactly like this, but it is typical for mine.

1. Take high levels of stress, sensory overload, etc.

2. Add in the uncontrollable urge to cry profusely.

3. Also add in the urge to scratch myself repeatedly until blood vessels show. Sometimes include punching myself in the forehead repeatedly.

4. If self-injury doesn't take place (or even if it does), I will start stimming. In my case, stimming will consist of either rocking, foot tapping or something else. Stimming is controlled and relieves stress, and is more desirable than self-harm.

Come to think of it. I should get a punching bag. Next time this happens (and it will, no doubt), I want to be able to hit something other than myself or the furniture.