My 30 Year Old Daughter Seems To Have Had A

My 30 year old daughter seems to have had a reaction to norflex prescribed for a 2 week headache and neck pain. Symptoms are head pressure, face tingling, high anxiety, fatigue, and inability to concentrate. She stopped taking it nearly 34 hours ago, yet still is complaining of symptoms, especially the head pressure. She never experienced this before. Question is how long should symptoms last if it is related to the norflex. She does not take anything else other than excedrine.