Disabled iPhone in USB Restricted Mode

I've been having storage trouble with my 16gb iPhone 6s for a while now. It hasn't been disabled in a pretty long time (last time was in August 2017 when I lost several VERY valuable photos the day after a trip down to LA. Needless to say I was pretty devastated after that). Tonight, I was trying to offload an app (the only app still installed on my phone) to clear up a bit of space but it wouldn't work, so I turned my phone off and back on. This has worked in the past. Upon restart, the dreaded 'iPhone is disabled; connect to iTunes" screen showed up. I plugged my phone into my computer to restore it. Luckily, I had backed it up less than 24 hours earlier. However, iTunes would not recognize my phone. It wouldn't even charge, and every time I plugged it in, it would vibrate 3 times. Upon further research, I found out that this is Apple's USB Restricted Mode, which you can only disable if you're actually in the phone. USB Restricted Mode basically disables USB if the phone hasn't been unlocked for an hour, which is very strange considering the phone HAD been unlocked less than an hour before this happened (it had been unlocked 1-2 minutes before). I'm completely stuck now. I can't connect my phone to iTunes since it's in USB Restricted Mode, but I can't disable USB Restricted Mode since my phone is disabled. I've just about given up with this phone. It doesn't look like there's anything I can do now except bring it into the Apple Store, which seems useless anyway since the iPhone ultimately still is in USB Restricted Mode. If anyone has any suggestions to fix this AT ALL, please tell me. Thank you so much.