3GS frozen, white flower on gray screen

I was reading an email and the white spiral flower in the center that usually means it is loading popped up, the entire screen went gray, and the flower turned solid white. The screen is completely frozen. I cannot shut it off the normal way or by holding the home and on button for 10 seconds. When I plugged it into the computer to sync, it makes the recharging chirp every 10 seconds but otherwise the screen is frozen. ITunes recognized my phone, but it just finished updating to 10.5. I am going to restart my computer to see if that changes anything. Anyone know what to do? I got this iPhone a month ago right before my applecare plan expired.