Ill in new house but nothing showing on my meters

Hi, everyone. I'm in the unfortunate situation of being ill in my new house, with symptoms clearing up after a few hours when I leave. I checked it with Acousticom 2 and PF5 meters before purchase, and have continued to check it with those and an EMI line meter. Magnetic, RF and EMI levels are low.  (I chose a detached fixer-upper in a quiet area for this reason.) Electrical levels vary but I can choose where to spend time and look into kill switches etc.

I have symptoms there (head pressure / twisting, insomnia, glands up, generally feeling dreadful) that I've had in only a couple of houses before and it was relieved by turning the electricity off. The levels I measured were never any different from other houses, so I didn't know the cause. Here, it doesn't seem to help to turn the electric off. I'm quite near a railway (about 20/30 metres), but it's a local third-rail line and electrical / magnetic readings towards the railway are low.

Assuming this is an electromagnetic issue (it feels like it), what can I do to pick up anything I've missed? Thanks so much for any help you can give me. My background health had been the best in years before I moved in here and I want to go back to that.

Have you tried measuring with a small/portable AM radio, listening for interference sounds coming from the speakers? That's usually a better indicator of something that will cause me symptoms than some EMF/RF meters.

Thank you - yes I did, but it was hard to make sense of it so I switched to an EMI line meter (since I was mainly using the radio to check for electromagnetic interference). How do you use it, please?

Well you are just listening for inteference... static, noise, buzzing that is not a radio station. Sometimes that noise affects the entire spectrum of the dial, in other cases it only affects some parts of the dial. For example, I would expect it to produce noise when near a computer monitor or most LED light bulbs.

Thank you. I'm fine around sources like that in general, so I need to find out what's different in this property.
Thank you again.