thanks for using health care magic.
sleep disturbance is known to cause gastritis, nausea. but you should also rule out other causes of gastritis with help of physician.
These symptoms are very common due to stress and anxiety.
you should try stress management
and relaxation therapy
like yoga, meditation and breathing exercise
. avoid caffeine, nicotine or alcohol.
if symptoms persist, you can consult psychiatrist
for detailed evaluation and treatment. doctor may prescribe anti anxiety drugs like buspiron or clonazepam for short term or antidepressants