Teething

I say give the Tylenol a try. He doesn't have to be running a temperature for it to work. He could just be in pain. They also sell a topical numbing type balm you can rub over his gums to try and help. It's in the baby section. I always froze melons and put them in a little net type thing and let them chew on it. They all loved the flavor and it helped their gums. Hope any of that helps! Good luck.