Thanks for your query to Healthcare Magic
I read your concern and your symptom of excess salivation and bloated stomach can be due to
1) Prenancy - But you have negative result for pregnancy
2) Reflux esophagitis
3) Irritable Bowel Syndrome
I would suggest you to consult a Gastroentrologist and get endoscopic study and rule out possibility of esophagitis and Irritable bowel syndrome .
Avoid caffines , NSIADS , and keep oral hygiene
by using mouthwash three times a day to reduce your symptoms.
You can ask me furthur if you have any queries.
Dr.J.Kingson John David