Phone won't connect to computer

So I have an iPhone 4, and last night I decided to update it on my computer (windows 8). I let my phone sync first, then started downloading the update. The update failed near the end (not due to internet loss, it just stopped randomly). My phone was left on the connect to iTunes screen, and my iTunes library was not detecting my phone anymore. I decided to unplug my phone and restarted my computer. It turned back on and I started by attempting to open iTunes, but it wouldn't open regularly or in safe mode. When I plugged in my phone, it made the windows sound of an external device being plugged in, but iTunes still would not open, and my phone was still on the connect to iTunes screen. After opening my task manager and closing any iTunes related processes, my iTunes still wouldn't open. Even my device manager couldn't detect that my phone was plugged in, despite the fact that every time I plugged or unplugged my phone, it would make the windows noise for external devices being plugged in.

I've only been able to open iTunes once since last night (I've reset my computer numerous times), but it still couldn't detect my phone. While iTunes was open, I made sure to check for updates, but it said it was up to date. I've also made sure that the issue is not a broken cord by using 3 different cords, in multiple different usb ports (that work for other things like my mouse).

Any help would be appreciated as my phone is completely unusable because it's half way through an update.