I can SO relate to you. My son gets his teeth in sets of two, and is miserable. It is so frustrating to hear those people that tell me their child got a tooth and they didn't even know that they were teething!
So first, yes, have the ear infection checked out. My son did get one while he was teething last and at that point it was hard to tell if he was crying for that or the teeth, although other than the medication, I treated it the same with him.
If my son was already in pain and worked up, there was nothing that could help him. What I would do was to give him Tylenol (Motrin if you choose, although I think they are supposed to be 6 months for that, so ask her doctor), and then would have to walk and shush, and bounce him till he calmed and was asleep. Usually, the Tylenol would help him stay asleep, plus he liked the treat :). When I knew he was having trouble, I would give him some Tylenol before the naps or bedtime and that - sometimes - would help him nap better and prevent the upset. The teething tablets didn't touch his pain, and we tried all of them in many different doses.
When I talked to my son's nurse about the pain, she said that for her own kids, the teething tablets did nothing, and while they may help for some discomfort, they don't get those kids that are truly in pain. She suggested the Tylenol. Also, I had a friend that had a difficult teether, and she was prescribed a compounded medication by her pediatrician. You may ask about that too.
Good luck to you!