Could it be teething?

My little guy is out of sorts - has been for over one week now. He had those bad weeks when we got back from California, and now this. I could be wrong, but perhaps he is teething? It could just be the reflux, I suppose, but he hasn't been feeling 100%. He has had a pretty drippy nose, but I don't think it is a cold (it is just clear). It could be allergies. He has been wanting to gnaw on everything, though, and he has been pretty drooly, too. He seems to be in pain/discomfort, especially at night, and tylenol seems to help. His tummy has been bothering him on and off - so who knows! I'm going to ask the doctor again on Monday when we go in for his 4 month checkup. Poor guy - I hope he starts feeling better soon! I don't know what I'm going to do if he actually pops a tooth through!