The endo did get back to me, and basically they were very sure that any allergic reaction would be at the injection site. GF started worrying about cellulitis, but there's no swelling or redness.
The caveat I should have mentioned is I did injure this knee, back in hs. I snapped the ligament partway, not enough to need surgery but it did dislocate the patella through swelling.
I went to the gym, the night of the T shot, and did the treadmill. BUT! I felt fine, then. Nothing out of the ordinary, knee felt okay. Swelling showed up next day.
It's improved today, although my knee is still creaky. Just... usually when my knee screws up I feel it in my actual knee, not a sudden swelling next to it?