My carbon Monoxide dectector went off im so scared.. help plz :(?

Most likely you have a faulty CO sensor, check on the back of it to see when the sensor replacement date is...i bet it is close to the date printed on the back. replace the CO alarm, and if you are still scared call a service tech to come check your furnace water heater and stove monday, crack the window in your bedroom open an inch and you will have enough ventilation air to be perfectly fine