Mary,
In the grand scheme of things... running a propane campstove in your kitchen to cook small meals isn't going to fill your apartment with CO to the point of a health risk. If you plan to keep the fuel-stove going for a while (you really shouldn't need to run it that long to prep food), crack open a window for a minute.
However, I would caution against trying to heat the living space with a propane heater... cooking a stew and heating an apartment are two totally different things. Same goes with using a barbeque indoors... it burns a lot more fuel and produces more CO in a shorter timeframe than a 'coleman' camp stove.
Having used propane and kerosene heaters in a garage in the winter... the key is circulating some fresh air, not running them too long, and paying attention to your body. Running the kerosene heater, and climbing under a car to do work on it, you would eventually feel yourself get a little light-headed. Heater gets turned off, and the door gets opened for a minute to give a quick shot of fresh air... and then everything is fine.