Im constantly either spitting or swallowing saliva. i also have been suffering from a constant headache. im struggling to keep food down. also smells can throw me off. ive had a blood test done which indicated vertigo and tummy bug.

Need to examine: It is not feasible to provide a meaningful opinion without taking additional history, physical examination and may be some tests. It would be prudent to see your doctor and discuss if you may be depressed. Counter-intuitive as it may seem, exercise may help. Start with low intensity exercise such as walking and gradually increase the intensity as tolerated. Wish you good health!