Putting myself in your shoes, I'd start with this to see if it works. If it works, I would EMF shield or faraday-treat an entire room of my house. There are paint options and wallpaper options. Even regular old tin foil is an option. If you use the interwebz from that room, you'll have to go a hardwire route for the telephone and net. Also, consider the possibility that it might originate from a permanent dental implant.

Faraday treating is no joke. You have to get every spot. I found a faraday cap, but I honestly don't think it would work the same way as the head net should. If you can prove to yourself that this method works, it'll be worth the time to do up a whole room. You can see for yourself how it works by putting a cellphone in a non-running microwave.

When you call the celly, it should not work, and that's how you know that it's working correctly. Put the celly in with your head net and give it a call to see if it rings. If there is no ringing, then it's shielding your head from any outside signals. Something like that might be superb for getting restful sleep.