I'm not sure if something else could have happened or not. That's probably best left for a doctor to decide. I can tell you, though, that I had an experience similar to yours when I got a filling done. I experienced pain near the tooth that had just gotten the filling. My dentist checked to make sure my tooth was filed down properly and it was. He also didn't believe that I had an infection, but he prescribed me antibiotics just in case. I went home and after a few days of experiencing more pain, I went back to the dentist. Once again, he couldn't find anything wrong. I went home and a few days later the pain was gone. I almost wonder if it's possible for a tooth to be sore just from being worked on, but then again I would think a dentist would know that. The unfortunate part for me was that I didn't have dental insurance
at the time. Because of the pain I experienced, I ended paying a lot more than I had expected. I hope you have found an answer to your problem!