Thanks for asking the query,
Heaviness in tongue and jaw pain
can be due to oral infections, neurological disorders, injuries to the mouth due to trauma, malignencies.
Excessive salivations occurs due to oral infections, Salivary gland
disorders, GIT disturbances, liver diseases, pancreatitis
, mouth ulcers and use of certain medications.
I would advise you to get a checkup done by a Physicisn and Oral and Maxillofacial Surgeon.
Take an OPG x-ray of the mouth. Look for any neurological disorders, salivary gland functioning, health of teeth & gums, oral mucosa
Meanwhile you can go for symptomatic treatment at home maintaining a good oral hygiene
, use of antiseptic mouthwash solution twice daily.
Hope this helps out.