Sounds like your leaving something out in your update process. What you describe doesn't make any sense. Did you start the update OTA and it asked you to plug into power to conserve battery? And was your power cord connected to your computer? If so was iTunes is set to automatically open when the iPhone is connected? And did you maybe start trying to update via iTunes while it was updating OTA? I don't know if that's even possible but I am thinking you are leaving something out. Explain exactly what you did, and what happened, step by step and then maybe someone can help you out. Just sounds too weird to be any normal occurence.