I'm installing Ubuntu fit the first time ever. I decided to do it alongside my Windows 7 installation.

I'm using Ubuntu 14.04 on a USB stick. Everything started fine, but after a while there's nothing on the screen but a spinning wheel. I've been watching it now for more than 15 minutes :

![spin-wheel](https://i.stack.imgur.com/9LG8k.jpg)

Do I have to worry? And in case there is a problem, how to fix it? Can I just reboot the computer and start over again?

**UPDATE**

The answer is much more silly than I thought. Apparently, the USB stick (physically) moved at some point during the install process and interrupted it.

As mentioned in the comments, all I had to do was to reboot the system and restart the installation all over again. It went smoothly. It even automatically detected how much space I assigned to each partition.

I hope this helps any one in the future.