When did your parents take the rubber sheet off of your bed?
The smoke detector would not detect carbon monoxide and if you have a carbon monoxide detector that is not turning black it will probably be something else - maybe dust or a small amount of smoke or steam from a cooking appliance. If it stops it will be something temporary. Maybe there is smoke blowing in from outside - have any of your neighbours had a yard fire?
Ctrl + Esc then C should get you there. Good Luck
