This is covered pretty clearly in the FAQ. Since the vendor has little help, do you have a backup of your Mac or can you make a backup so that if you need to erase and reinstall the OS, at least you have that option?
https://github.com/SelfControlApp/selfcontrol/wiki/FAQ
Q: How do I disable SelfControl once it has started?
You can't. That's the idea. Just wait.
"But, but but..." you say.
Seriously, chill out. It's not the end of the world.
The timer will run out and the internet will come back again. In the meantime, you may find comfort in curling up in a ball under your desk and rocking back and forth for a while.
Q: I deleted the application, will that do anything?
No. (Except maybe cause problems with the block disappearing at the proper time. Don't do it!)
Q: I did some stuff with the terminal that I read on a cool tech site, but it didn't work, what do I do now?
We don't know what you did or why you would follow instructions found on the internet before reading this FAQ. Lesson learned right? Good luck!
So for the good luck part, the most helpful advice would be to reinstall the latest version of the app (or the current version you installed if you still have the installer) - downloading it from another computer if needed and hope that when the timer goes to 0 like the FAQ describes - you can then unblock things before trying to uninstall it once the block period has expired.