at such young age makes you susceptible to a variety of oral & oropharyngeal diseases including malignancies. Family history is definitely a risk factor. My advice for you would be to use a good mouthwash /oral rinse to maintain the oral hygiene( having gingivitis
is an indication of poor oral hygiene) avoid further tobacco chewing , have a balanced diet which includes plenty of fruits and vegetables( to provide you with the necessary vitamins
& minerals that a growing boy needs) and a multivitamin
supplement . The condition should improve with stoppage of the tobacco chewing .You may consult an ENT Specialist
for further advice after proper checkup.