In case people want another set of clear instructions on manually updating, you'll find one at Android Central. (Sorry, I'm new and I can't post the url)
My heart was racing (my first Android phone), but it was really very simple - just take the time to read what's on the phone's screen - there are instructions… And for anyone thinking the update isn't working - be patient, even after the green progress bar finishes, it still takes some time for it to complete. My phone rebooted itself 2 or 3 times and it was finished.
Hope some of this helps.