I don't think three days is long enough, personally. Have you already reinstalled the pad and carpet? If not, consider renting a dehumidifier or two, depending upon the size of your home. Set the unit on your kitchen counter and let it drain into a plugged sink, and you can see how much water it sucks out of the air.
If you do have mold and mildew in your carpet, you are going to have to have it cleaned, and I would have a professional do that for you. The rental machines don't do it well enough.
Identifying other sources could be tough, without seeing (smelling) the house. Be water and ask yourself where you would go. bleach is your friend here if used wisely and carefully.