My friend's chihuahua tried to go down her two stairs and jumped from the second one and broke her front paw. We took her to the vet and they put a cast on it and gave her some pain medication. She just called me because she is nervous about the way she is acting. She says she keeps putting her head up and is like real wobbly, then her other legs get wobbly and she is shakey. I told her it is probably from the medication, but I just wanted to get someone elses opinion.
I wouldnt be real concerned. Since the vet checked the dog out and the dog is also on pain meds, Im sure its just the meds. I recently had my basset hound spade and she was all wobbly and would lift her head, wobble and set it back down. She didnt really do anything then just lay where you set her down and was pretty out of it. By tomorrow, I would expect your friends dog to be up and feeling better. Good luck and take care!
just a note of caution; perhaps ypur friend needs to go to home depot or something and get some plastic lattice and screen the steps along the ledges so it wont get hurt again. and perhaps other steps too. ;)