Warning Signs Someone's Past Trauma Is Triggered

There are a few key actions that are signs someone's past trauma has been triggered.
These warning signs include, but are not exclusive to
Giving a big reaction to something  you considered "small"
Starring off into space " zoning out"
Presents self-soothing actions
Example-Rocking back and fourth, picking at skin, playing with string, a zipper etc.
Avoids physical contact
They go silent, wont talk and or even give a physical response, such as a  shoulder shrug.