Whats Wrong With My Dog ! :(?

My mom had took the dog to the groomers and when we got him back he seemed okay. But when we got home he was acting very strange. Right now its 2 days later and he doesnt want to go on a walk. When we do try and walk he just lays down every time we go past like 3 sidewalk blocks. He is eating though. He lays down all day doesnt bark anymore and is shaking a little. Were taking him to the vet very soon. My dad thinks its just because he has a small cut on his tail.