Anxious about spaying of rescue dog

[Bearpaws64]

I've been fostering a little staffie for three weeks, in less than a hours time I have to take her back to rescue centre (over an hours drive) for an overnight stay before she is spayed and has a lump removed tomorrow morning.
Going to pick her up tomorrow afternoon and finalize adoption. Trouble is she gets very stressed in kennels, and has just settled in lovely with us, I'm worried this experience is going to set her right back.
I'm not looking forward to the spay aftercare either!
Anyone else had this experience with a rescue? Any insights to what to expect?

My friend had a similar sitch with her bitch who wasn’t yet super settled and could be very anxious.
She was surprisingly ok, a little bit of toilet training regression but coped with it all very well

We were really worried about our Romanian having her spay, however in her case it was as well we did as she basically had a pyometra despite supposedly already being spayed (long story, relates to appalling vet "care" in Romania where he womb was mangled rather than removed).

Dog are incredible - they bounce back from the most weird of situation. I'd expect her to be worried when you pick her up, but I'd basically assume you're starting the 3 day / 3 week / 3 month routine from scratch in this scenario and go back to the beginning with her. She'll need pain relief, which really does help.

We weren't warned that the first poop post-spay is a much like bearing down after a c-section (i.e. painful!) so our first dog screamed when she did that which was a shock to both us and her..... The Romanian didn't bat an eyelid though!!

The aftercare isn't too bad as long as they aren't worrying the stitches. Both ours slept a lot and within a few days were up and wanting to play which was difficult because they needed to rest still!