Thank you, neko1 and Jenn. We went in to see the vet, and Sydney's blood pressure was normal this time, so we're not starting him on amlodipine at this point.

I got copies of Sydney's records, and I'm going to call the other vet and see what she thinks.

Thanks, Jenn, from Sydney and me and all the others for the good wishes and hugs and lovies and skritchies (which have been delivered)!