DDog, 8, didn't want to walk upstairs to bed last night and sat at the bottom so I went and carried him up, he usually bounds up 2 at a time. I thought he was just tired after slightly more walks than usual- Friday just gone he had his second shot of painkiller which lasts a month and he was happily up for going a little further than usual yesterday but I'm only talking an extra 15 mins a couple of walks.
This morning he struggled to get out of bed. He usually is 0-100mph and super happy/waggy. Instead he plodded three wobbly steps, thought better of it and went back to bed. I got up to check on him and he was trembling all over, giving me big sad whites-of-the eyes. This uncontrollable trembling continued for 15 mins so I rang the vet and they said fetch him straight away. He needed carrying to the car and when put down for a wee just stood wobbly and hunched up. Vet ran bloods, checked temp, breathing, blood sugar, hydration, heart etc and all are normal. He stopped shaking about a couple of hours after he woke up but he's still very subdued and drowsy, he's literally stayed curled up all day and had been very quiet. He's a bit twitchy and it's like he's trying to sleep but something keeps jolting him.
No vomiting or diarrhea and will eat treats.
Vet said a reaction to the painkiller injection on Friday would have happened before now. One other thing I mentioned to the vet was our grass out back had Roundup weedkiller sprayed onto it last Thurs. Last night (Mon) was the first time I'd let him out there and he'd been raggying his toy. Vet said a reaction to that would be more severe, with seizures, vomiting etc. Packaging says safe for pets when dried. But I'm wondering would it be possible for residue or 4 day old dried roundup to cause non-deadly illness/lethargy/trembling? The vet seems stumped and just said he's fine as all obs ok, but he's still really not himself at all.
Do older dogs start to have "off days" maybe? Concerned enough to request a second opinion I think... What would you think/do?