Dalmatians

Hi everyone....my 4 yr old male Dalmatian just woke up whinning and acting strange. He is pacing and his tail is down...his tail always wags--24/7....this is so unlike him. Thought maybe he was having some tummy issues so I let him out...again the pacing, he did go pee though. He came back inside and sat with me in the chair ...shaking,panting and talking to me. He is now lying down in the kitchen on the tile and will not come back upstairs...what are signs of shock? pain? Never had to deal with this ....any imfo will be appreciated.