wat should i do?

find a new dr? go back to the same dr until u get answers? take him to the er? google his symptoms?

Take his temp a few times over night. Loosen up the covers, or try to loosen up a flannel nightie, and add 2 soft lighter blankets. Give lots of apple juice and diluted orange juice, pediatlyte drink, and liquid tylenol. Put some vicks on the chest and boil water with after turning off the flame or heat and add vicks just bring it to the room he's in or if near the kitchen let him sleep on the couch and let the steamy air vapors go in the room. Its worked for mine a bunch of times. Vicks makes oil too. Like warm up a quart of water to a tbsp. of oil / vicks.

Is he taking fluids? This is critically important. He can miss a few meals but must drink. Did the doc say anything about strep? What did they give you for meds? Did they nebulize him for the congestion or mention wheezing? Try to loosen up that cough with humid air (shower) or even a walk outside in the cold. I'd call the nurse line again.

If he's getting worse, I would just take him into the ER. He could be dehydrated from having diarrhea and if it's getting worse, then he needs different medications. They need to run tests to find out what's going on. If it was me, I'd just take him in ASAP because then they can get things going so he can get better and possibly give him some IV fluids to get him hydrated.
I hope you're able to get him feeling better!
Best wishes!