Re: EMF sensitivity could be real.
Or the smart meter installer partially blocked an exhaust vent, and the dude/tte who replaced the meter unblocked the vent. The first part happened to a local here in Sonoma. If their carbon dioxide detector hadn't gone off, two adults and four kids would probably be dead.
(Hint: Get modern exhaust on all your ventilated gas appliances ... Part of the reason the bit on the outside is as large as it is is so it can't be blocked very easily.)
My money is on the ghost ... but only because I got good odds. Very good odds.