IPhone not connecting to computer or itunes?

I resently got more music on my itunes library so I plugged my iphone 4S in to the computer to get the music on the phone. When I plug it in, the computer makes the noise saying it is plugged in. 3 seconds later it says it has been unplugged. It switches from being plugged in to not being plugged in for a while. When I do get it to be plugged in, my computer will not download the pictures from the phone saying it could only import some of them. Then where the USB symbol is on my computer and a little bubble pops up informing me that the device is not recognized. When I go to itunes it gives me a warning saying the device didn't connect and for me to unplug and try to reconnect again. I've been in my devices panel and tried clicking repair on my iPhone, and it did it, but nothing happened after. I also tried looking at the properties of my USB connector but I don't know what I'm looking for.

Do you think it's my iPhone or my computer acting up? Please help, its starting to make me mad.

Added (1). I have windows 8

Have you tried shutting down the computer, and leaving it powered off for at least 30 seconds, then restart it and try connecting the iPhone?

Try resetting the iPhone by holding down the sleep/wake and home buttons until you see the Apple logo, ignore the "Slide to Power off" screen?

(Both of the previous steps could be done simultaneously. Shut down the computer, reset the iPhone, and then turn the computer back on)

Also, you may want to try "Run as Administrator" by right-clicking the iTunes Application BEFORE opening iTunes.

Once you have already restarted the iPhone, Computer and tried and new USB port, try the following:

1. Click Start
2. Search "Device Manager"
3. Click on the button, just below the menu bar, that says "Scan for Hardware Changes"

If your iPhone still is unresponsive, try this:

1. Click Start
2. Search "Device Manager"
3. In "Device Manager" click "Universal Serial Bus Controllers"
4. Right click on any sub-section that is a "controller" and click "uninstall"
- This will be reinstalled automatically, if you have an internet connection, once your computer restarts.
5. Restart your computer

If none of these work, feel free to message me and I'll shoot you some more ideas.

Best of luck!