My dental crown feels strange when touched. Advice?

I recently had an existing crown replaced and the adjacent top incisor crowned. The newly crowned tooth had a root canal performed some 20 years ago. It now feels very odd when touched. It also mildly aches and I have an occasional slight burning sensation. The dentist has tested the crown for mobility and taken an X-Ray. He said everything is normal and that crowns do feel different. The other crowned tooth feels fine (it is now on its 3rd crown). Any advice will be greatly appreciated.