My German shepherd has randomly started yelping in pain. It happened first when I was giving him a tablet before feeding him (he's been having some bowl problems) and as I was leaning over him to give it to him he yelped in pain, I thought I must have stepped on his foot or something but was sure I hadnt. He ate all his dinner. I shrugged it off, and then about 15 minutes later we were in the park and he was fine, just perky and normal, when he randomly cried again, I thought he must have stepped on something! Checked all his paws, felt all down his legs looking for signs of pain, absolutely nothing! Walked home like normal. Then later in the evening he was being strange, he looked depressed, he yelped in pain again, I started poking and prodding all over his body to find see if i'd hit the painful spot and got nothing, he came over to see me and I rubbed his shoulder and he shrunk away and cried in pain again! Every time I ask him to sit he lays down on the floor and hides, my dad said to see if he'll eat cheese (he loves cheese) and he wouldn't eat it. My nan touched his paw and he yelped. But when I touched them after he didn't care. He's restless, he normally sleeps upstairs and never goes downstairs unless he wants to go in the garden, now he'll follow me upstairs, lay down, get right back up and pace back and forth downstairs, I'm so worried, I'm gonna take him to the vets tomorrow but can anyone give me any advice?