Can white semi thick odorless discharge and itchy vagina be caused simply by stress? or from drinking a lot of caffeine soda? could it go away by water

Other causes: You are describing a vaginal yeast infection. It is easily treated with over-the-counter yeast treatment, such as monistat. It is not caused by stress or drinking caffeine. It is caused by an alteration of the normal vaginal bacteria. A common cause in your age group is related to the use of birth control pills. Talk with your doctor about this as a possible cause.

No: Most likely a vaginal yeast infection that you can treat with over the counter monistat. If that does not knock it out, please see a gynecologist or your family doctor. Good luck to you.