Post-surgery care concerns

I have a 5-, almost 6-month golden retriever puppy. About a week and a half ago he had emergency surgery to remove a cat toy from his intestine. I didn't know he had eaten it, otherwise would have taken him to the vet right away to have vomiting induced. Because of the particular toy it was, I know it was in his system for more than a month before being removed.

I had noticed for about a week before the surgery he was acting strangely. He would no longer settle in his play pen, would panic when I left the room, and started waking up about an hour earlier than usual. He had softish stools, and was going more frequently than he had been previously, and had pretty bad flatulence. This all coincided with my returning to work after a 2-week holiday break, a gradual food change and some pretty bad teething, so I wrote it off. This was about 3 weeks after he had eaten the toy, and in those 3 weeks he had been completely normal.

He's been home after surgery for just over a week. For the first week I kept him on a higher dose of the sedative meds the vet sent him home with and he pretty much slept in his crate all day.

The past 2 days I've cut back on the meds and all of the behaviors he was exhibiting the week before he went in for surgery have returned. He is pooping more than normal, farting, unable to settle, and is waking up in the wee hours of the morning. When I let him out of his crate he jumps all over stuff and plays really aggressively, which the vet has specifically told me to avoid. If I leave him crated, he barks and scratches in the crate and I'm worried he's going to hurt himself.

I'm at a loss. I don't know how to handle this in the interim while his incision heals, and I'm worried it means something larger is wrong since the surgery has clearly not fixed this. Is this just normal puppy stuff?

Let me know if this makes sense. I'm so tired from the lack of sleep. Thanks in advance.