Tooth sensitivity

[Anna_Anna]

I had two small fillings on upper middle tooth (probably called upper 9, not sure) 4 months ago. The tooth didn't bother me at all before the treatment. After the treatment it really hurt first day, then got better. But the next day I realised that the filling on the right (where it connects with other large middle tooth that has no fillings) is too high so it was giving me a lot of discomfort, even jaw pain. It took me 3 visits to the dentist over the course of 1 month to make it low enough that there is no teeth contact on the filling but even since the treatment I have a really bad sensitivity on the right side of that tooth (border with number upper 8) on pressure and when I floss. It doesn't seem to be getting better. I went back to the dentist and had an x-ray done. He has no idea why it hurts. X-ray is attached. Looking on x-ray and the description does anyone know why it aches and what I should do? Thanks