Never been to Briarwood specifically but I've investigated a few old psychiatric sites in the UK and the east wing thing really resonates with me. In my experience those older hospital buildings almost always have one section that feels distinctly worse than the rest, and its usually connected to the more "intensive" treatment areas from what I've read up on.
Did you get anything on camera or audio when you were there? I'm just getting into this properly after years of watching from the sidelines and I'm trying to work out what equipment is actually worth bringing to a location like that. Also wondering if the feeling you got was more like a pressure or more of a sudden dread that hits you when you cross into a particular space, because I've heard people describe both at similar locations and I'm curious whether they might be picking up on different things.
Would love to hear more detail about what actually happened if you're willing to share.