This woman who was telling you that you aren't fast enough & to work out a system & who seemed to be in charge ...
I've worked in a few nursing homes, & people were always anxious to show me The System they'd perfected so I'd hit the ground running. I mean, who sits someone in front of a filing cabinet and complaints that they're slow in working out a filing system?

I think you did great--if you get fired, I'll write you a recommendation.

Roadie