Yes, PLEASE go to the vet..he could have a blockage or his kidneys are no longer able to produce urine. Has he gotten into anything like licked antifreeze from the garage floor or any other toxins? If us humans were unable to pee, imagine how uncomfortable we would be and we would definitely rush ourselves into the ER....please know that this is urgent and give the same kindness to your dog.
Welcome.....Not necessarily....You don't give much information, but this doesn't have to be Kidney's shutting down...Has your dog been diagnosed w/Kidney failure or disease?
To me this indicates either crystals or stones blocking the passage of urine...Actually, this is very common, but you MUST seek help to clear the blockage.....Unable to pee is an emergency.....Please call your Vet or head to an Emergency Center ASAP.....Good luck and let us know....Karla
Nit much info. Could be any number if things,possible bladder infection.
You really need to get the dog to the Vet ASAP