Under no circumstance, no matter what the disease is, self-medication should be advised. Stress is very hard to define, let alone decide by yourself how to make it disappear with medication of your choice.
Most of the time it's easier to just swallow a pill than to get a doctor's appointment. But the dangers of self medication are worse. It can lead to severe medical consequences due to the incorrect dosage and choice of medication and to risk of abuse.
If you are not a physician, you cannot know what stress is about or different types that may exist, each with their own symptons and treatment approaches.
An eating disorder is something that you think you are in control of, but in reality it controls you. A diet is something that you can control and know that you are in control of.
You would want to talk to her in the back and use a moderate tone and show her the schedule showing that she was booked for a appointment another day and time. You then tell her that you are sorry for any inconvenience and that you will be expecting her on the right day of her appointment.
The Valsalva maneuver is performed by forcibly exhaling against a closed airway. Maneuver variations can be used either in medicine, as a test of cardiac function and autonomic nervous control of the heart. A modified version is done by expiring against a closed glottis. This will bring forth the cardiovascular responses but will not force air into the eustachian tubes.