Yep. If I understand what you are referring to, it seems a very heavy feeling, a sort of shutdown. For me, this is a type of/level of shutdown which results in a draggy, brain-foggy, heavy-limbed torpor, a sort of stupor in which everything feels thick, sloggy, hard to move through.
It is caused by brain overwork, overwhelm. The brain is now on "energy-save mode."
What can bring it on, for me anyway:
Emotional dysregulation (due to a difficult therapy session, loss of loved one, dealing with a diagnosis, etc.)
Task performance overload (taking neuropsych testing, IQ testing, running too many errands with the bus, etc.)
Sensory hoopla draining the brain (a mall, crying baby at a restaurant, etc.)
These alone, or any combination of these trigger deep, heavy-limbed torpor shutdowns.
If anything taxes me further in thyou s state, Autistics c catatonia (being stuck, unable to move or speak for a while) is the result.
Solitude heals. Good sensory input such as swimming, hiking in nature, swinging on a swing set, or bouncing on a trampoline can hop clear this state. Stay hydrated. More solitude. Go into your sanctuary, both in terms of physical success cal space, and into your inner world, and find your peace. Meditate if you are able. Eat simple foods that bring you happiness. More solitude and quietude to decompress.
Give it time.... and give the time, some time.