'obsessive' behaviors are called compulsions, and are seen as a part of obsessive-compulsive disorders. burping comes from stomach, and not from lungs. so if you are sure its a burp, its unlikely that you have 'early lung cancer'. the swollen lymph nodes
and dry tongue might be secondary manifestations of an open mouth breathing
. also, too much deep breathing might cause hyperventilation
which makes you feel giddy, fatigued and sometimes nauseated.
however, there is no alternative to a physical consultation with a doctor.i believe you should consult a qualified physician near your place. he/she should get you evaluated adequately for any underlying organic cause, and can arrange for appropriate referral thereafter, in case you need any.
hope this helps.
Dr. A. Rao Kavoor