Skyra is a 25-year-old female. She presents to your clinic due to work responsibilities that she has been unable to fulfill. She is expected to travel to Dallas, Texas from North Carolina every other month to serve as liaison between her company and an IT company. She always waits until the last minute to book her flight. She usually will not sleep the night before a flight and if she does her sleep is disturbed by nightmares of something going wrong during the flight. She has missed her flight twice at significant financial impact to her company. During her last flight, she experienced a panic attack. What is her most likely diagnosis?