Location of infection in the gums

Last week I developed excruciating nerve pain on the whole RIGHT side of my mouth. The pain was like that experienced in Trigeminal Neuralgia (TGN). It wasn't a toothache type of pain. So I went to my dentist and after taking out an OPG X-Ray, the dentist looked at it and said that the problem was that there was an infection in the lower jaw that was a result of dislodged filling in the middle of the lower two teeth. This infection and the filling were irritating the nerves and causing the pain. Just to get a second opinion, I went to another of my known dentists. After looking at the X-Ray, he said that the culprit was indeed the infection, but it was infection in the upper jaw, the sinus area near the roots of the last molar and premolar. It was this infection that was irritating the nerves and causing the pain. Now I am confused. So I have uploaded my OPG X-Ray here: http://s24.postimg.org/c9ce3x0ph/Dental_X_Ray_OPG_15_March_2016_b.jpg Could you please look at it and tell me where exactly is the infection, top or bottom jaw and if it really is the infection which is causing the excruciating nerve pain. Thank you so much