Day 6 Post-Amputation – shivering and limping in hind legs. Is this Normal?

Yesterday, on Day 6 post-amputation, my dog’s back legs started shivering, and his activity level has noticeably reduced. He also seems uncomfortable on his back legs and has developed a slight limp on his left hind leg and is not walking much now, likely due to pain.

Our vet initially advised painkillers for only five days, so we stopped them on the morning of Day 6. However, after consulting another vet, we were told to continue the painkillers for another week, so we’ve resumed them. This vet also mentioned that the shivering and limp are normal.

Until now, he’s been quite active, and we’ve been taking him on very short, slow car rides to a small garden where he relieves himself.

I’m really worried. Has anyone else experienced this with their tripod dog? Any advice or reassurance would be greatly appreciated.