I had a similar thing happen before, except it was Windows 7, I turned on my laptop and it asked me which OS I wanted to use, it wasn't common for it to do that so I pressed "Windows 7", then it showed the "Starting Windows..." thing, and all of a sudden it freezes on it and starts beeping at me, no clicking though, so I pressed the power button and held it to turn it off, and when it came back on it was fine.
So your laptop might've crashed for a bit or something.