Thank you again, folks!
Just to give an update...
She went through the set of IV injections (we didn't do adequin (spell?) or hock injection). Now on supplements I got from my vet (very similar to Smartpack joint), and I put BOTs on every night (will stop for a week next week). Vet said he'd wait on IM injections or hock injections unless it gets worse. I do keep Previcox too in stock (just in case), but I didn't give her any as of yet.
I started riding her again (in fact after the 1st shot per vet's advise). Knock on wood so far. I don't ride whole lot, but we do both - trot and canter, and she doesn't seem to have much problems with picking leads and all, and is not resistant to what I ask for.