I got myself locked out of my house once, had to sit outside for two hours after trying so many different antics to get inside. And yes, I left my cellphone inside as well... So I had to wait for my parents to return before I could be let back inside.
One such antic was when the phone was ringing inside and when the answering machine picked up I could hear it was my mom asking if I was there, I then saw my cat staring at me through the window on the front door and I begged her to get the phone - I was very desperate - and she went up the stairs. Finally! She was going to get the phone! No, wait... She's heading into my bedroom... God darn you cat! Eventually my mom assumed I was sleeping and hung up.