Sensitivity can be either localised in one tooth or can be generalised (not a particular tooth but all teeth in general). Considering your age generalised sensitivity is rare as the major cause for it is advanced gum problems. If it is localised tooth and if you find that tooth to be decayed get it filled.
Next Steps
Visit a dentist for thorough dental examination to rule out any pathology and come to a diagnosis.
Health Tips
Using any kind of sensitivity toothpaste may provide temporary relief but it might also mask the root cause for which it is causing sensitivity.