Why can't I change my brush settings for the Healing Brush in Photoshop CC (2017)?

I've selected the healing brush in Photoshop CC 2017 (mode: normal; source: sampled; sample: current and below; pen pressure for size OFF). When I open the Brush panel, all options are grayed out.  I guess the first question I should ask is: is this normal behavior?  It seems like when I select pen pressure on or off, I get the same response.  To me, this implies that there is some brush setting (shape dynamics? transfer mode?) that is looking at pen pressure.

So, assuming I shouldn't see a grayed-out Brushes panel: how can I edit my brush settings for the Healing Brush? I've read some posts elsewhere to suggest I need to completely reinstall PS to make this work?? I'd like to avoid that. Am I missing something obvious? Do brush settings not apply to the healing brush? I have no problem with brush settings for the clone stamp (e.g.).