Namaskaram,
Brown spots that you noticed can be because of stains or the dental caries . you need to visit a dentist so that a clinical examination is necessary for a right diagnosis . Sensitivity that you are experiencing can be either because of gingivitis or the deep dental caries . You need to get the cavities filled along with a professional scaling and deep cleaning so that the condition does not worsen.
Team Shambhala.
Answered2019-09-18 10:53:49
Let others know if this answer was helpful