Firmware upgrade inconvenience!

[justiceanthony]

Hello, a firmware upgrade was downloaded for my GALAXY S4 after I turned it on for the first time yesterday. I want to know whether the phone automatically restarts even when I don't tap the "Okay / Yes" button on the "Device will restart" message (the message you get after tapping "install" on the firmware upgrade page). My phone automatically restarted even when I hadn't clicked the "okay" button. I was downloading something in the background, so I wanted to wait till download had completed before clicking the "okay" button, but the phone automatically restarted, terminating my download. Please tell me if this is normal with the S4? If not, what could be the cause? Thanks.