When Inca had her first injection, we had a similar reaction. She howled when the injection went in but she is a bit of a drama queen so I didn't think too much about it. Every time we touched her, she howled, and when it came to eating her tea, she couldn't get her head down far enough to get anywhere near to it. She was depressed and very obviously uncomfortable. We took her to the emergency vet, who gave her a metacam injection and further injection (can't remember what). He said that some puppies have a reaction to the injection but I firmly believe that it was put into the wrong place. I was very reluctant to take her back to the same practice for her second injection but did and she had no further reaction. I did however insist on another vet to do the injection. When it came to being microchipped, I was afraid we would have a worse reaction to a bigger needle but she needed it done in order to send some blood to America. Neither of my poodles reacted to this much bigger needle. So, I think some of your poodle's symptoms could be a reaction to the injection but others need further investigation. I would get a second opinion from another vet practice.