Sounds like either a) a poltergeist, or b) the effects of carbon monoxide poisoning.
I'd call a gas engineer first - could be a problem with an old boiler or blocked flue (which channels out used gas, hence no smell, it's carbon monoxide now) This is very different than a gas leak, but just as deadly. More so, actually, as there's no smell to warn you.
If that doesn't work out, Mulder and Scully would be the next port of call.
But definitely the gas engineer first.
I'd call a gas engineer first - could be a problem with an old boiler or blocked flue (which channels out used gas, hence no smell, it's carbon monoxide now) This is very different than a gas leak, but just as deadly. More so, actually, as there's no smell to warn you.
If that doesn't work out, Mulder and Scully would be the next port of call.
But definitely the gas engineer first.