I need help restoring my iPhone

This happened yesterday when I changed my passcode but forgot my new passcode and I looked up what to do and it said I had options 1. If i had it synced with Itunes I could restore everything (I don't have it synced) 2. If I had it synced with iCloud I could restore everything (I don't have it synced) 3. Recovery Mode, I figured to use this as it was my only option it said to turn off my iPhone and hold the home button and plug my phone into my pc via USB and I did, it came up with an icon of my iPhone connecting to Itunes and Itunes opened on my pc, it found out my iPhone was in recovery mode and I clicked restore and it said I needed to download an update which I am fine with but everytime I try to download the update my iPhone randomly turns on and causes the download on my pc to stop.

I am wondering can I fix it myself or do something or should i bring it into my local phone shop and see if they can do anything about it. I don't mind losing everything but I would prefer to keep it. Another thing i found thats weird is that it said i had to get ios 8.3 even though its already on my iPhone