It sounds like you went completely cold turkey, and it worked fairly well. You truly had no electronic use outside of work?
If you can manage that, and you live alone, there is a simple solution: unplug your router and modem after work. Plug it back in before work. Then put your devices in a drawer.
This has actually worked for me, where other blocking systems have failed. The physicality and totally of the unplug do it. But it is usually difficult as most people need some access at home. If you truly don’t, this total block option opens for you. You’ll prob have to temporarily give up your data plan as well.
There are other options to block in software, or at a technical level on the router.
You can track your success with this plan on paper. Maybe one piece of paper always on your desk. Write a description of why you’re doing it, then make a “don’t break the chain” calendar and mark it off for each day. You can use this as a log too of how it’s going.
The advantage this system has is you have to consciously choose to plug in, unlike digital systems where you can sort of drift into disabling it. If needed, you can also keep a physical log book on the router to write your checkins, or have a friend try calling you to see if it’s working. (You can keep a voice plan on your phone. Without data or wifi the phone won’t be very addictive most likely)