I also have trouble sleeping with closed windows, especially when it's colder outside. It's really nice to cuddle up under a heavy warm blanket when it's a bit

I also have trouble sleeping with closed windows, especially when it's colder outside. It's really nice to cuddle up under a heavy warm blanket when it's a bit colder in the room, tho it can make getting up in the morning a real pita when the room cooled out way too much. I wonder if the "suffocating feeling" without an open window might be the result of higher CO2 concentration in the bedroom if it isn't aired regularly enough? Might be worse for smaller rooms without proper ventilation and more noticeable due to the sleeping position being lower than regular standing/sitting? There's also this old trope of plants in the bedroom supposedly being a very bad thing.