Sounds like teething and typical "happy hour" at your house at 5pm:) Timing's right, and not all kids get swollen gums or are "unhappy" all the time while teething -- it takes a very long time to complete all those teeth. Also, babies like to "mark" things they love (you:) ) with their scent because they are so scent oriented their first year -- this is possibly the cheek rub/chest/head-shake.
My kids hated the cold teethers, but loved the smooth water-filled ones at room temperature, combined with teething drops and sometimes infant tylenol. They hated the bumpy teethers at any temp, the vibrating ones, and the wet washcloth was totally out. But try what you haven't until you find what he likes.
When to give the tylenol? -- when he gets very close to his "breaking" point (you know the signs, mom:) ) and you'll see a behavior "calm" in around 15-20 min. Good luck this year with the teething:)