It's not because you share your room.
Many people notice that their asthma is worse at night. Doctors don't really know why but think it may have something to do with the body's natural rhythm and release of different hormones and chemicals that is highest in the morning and then tapers off through the day.
It's also possible that you have allergies to something in your room or your bedding (like dust mites), so you should be sure that you've done everything possible to minimize exposure to allergens and triggers in the room where you sleep.
