Kourtney Kardashian suffered a claustrophobia attack as she arrived at Los Angeles International Airport.

The reality TV star - who is currently pregnant with her second child - started to get anxious while she was going through customs at LAX and had to take deep breaths to calm her down.

"Wow claustrophobia attack in customs at the airport. Not fun. Ahhhhh deep breath! (sic)" she wrote on her Twitter. However, Kourtney - who has two-year-old son Mason with her partner Scott Disick - soon recovered and celebrated her 33rd birthday yesterday with a takeaway burger.

"Just had IN N OUT for the first time! Can u believe it?! I asked @ScottDisick to get it for me tonight for a relaxing birthday din din. Yum. (sic)" she wrote. She also thanked everyone for their well wishes on her special day, saying, "Thank you all so much for the birthday wishes! Love u all so much! (sic)"

Kourtney has been suffering from claustrophobia since falling pregnant and recently took to her Twitter page to ask for advice: "Deep breath. Been struggling a little with claustrophobia ... any other preggos feel that way too? (sic)"

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