Forgotten Password

Earlier today I changed my password and typed it in later on, but it was incorrect. I tried similar combinations but my iPhone was disabled. I spoke to somebody from Apple Support and they showed me the Find my iPhone method but my phone didn't show up. He told me to get access to a computer and try the iTunes method but I've never synced my phone to it before. I also found out about the Recovery Mode method but for some reason, it says that I can't connect my phone to the computer with the USB cable unless it's unlocked. How else should I unlock it?