If we realize that a session has been heavy and are begining to experience some of what you are saying, we usually tell T right then. She will tell us that she is available if we need her, reminds us of our tools in our toolbox, helps us do some breathing before we leave.
She has been good at doing a check in about 5-10 minutes before session is over and asks how we are doing. If we are ok to drive home. She also does some winding down so we never leave in a bad place.
It took us to tell her we needed that. We came to realize that our T isn't a mind reader after all--

imagine that we said!!!
wi