My little Indi was spayed last week and she is 6 months old.
She was quite groggy and tired for the first 2 days but was back to her usual self not long after that! although a little sore... try not to let her jump too much after her op although she will be excited to see you
Indi had her stitches out yesterday (10 days after Op) and her incision has healed perfectly. She didn't try to bite her stitches the whole time either which I was worried about. She did lick them for a first couple of days but I was told that's normal, as long as its not excessive licking.
Goodluck and remember they are professionals and will take great care of your baby