Why I feel stuffy when my dryer is running?
Looking at the this parts digram, this model appears to be a combination washer dryer with an electric dryer, so it's not likely to be carbon monoxide.    Possibly the dryer is not correctly vented to the outside, so it is pumping warm moist air into your house.   First, make sure the lint trap on the dryer (in a slot at the bottom of the door opening) is clean.    If the dryer is vented to the outside (you should see a vent on the outside of the house near the dryer), the vent pipe may be blocked.   If it's not vented to the outside, you may want to check with your landlord to have that corrected.