No wet diaper

My 11 month old has the stomach bug. We went to the doctor this morning because he was refusing to eat or drink and he went all night without a wet diaper. He has had diarrhea 6 times since last night, but has not peed. The dr told me to give him a teaspoon of pedialyte every 15 min and we have been doing so all morning. He’s also had 2 pedialyte popsicles and some chicken noodle soup. As soon as he finished his soup he immediately had diarrhea again, but still no wet diaper. He’s been asleep for around 2 hours now and his diaper is still completely dry! Should I be worried? Could he be dehydrated?