3. Warped Walls - Moldy Walls
If you notice that your wall looks like it has water damage or mold then it's likely molded. Sometimes the clearest sign that you have mold is that you can actually see it. You should always be cautious with water damage on your walls and ceiling and find the leak. If you have persistent leaks then you will end up with mold.
4. Persistent Illness
Have you recently been fighting a persistent illness? Having mold in your house can cause you to have respiratory illnesses and that is one clear sign that you have mold in your house.
5. Fungus around the house such as a couch or carpets
Mildew is attracted to leather and wood that is moist. It's very common for you to get moldy couches or carpets when you have mold in your house because it attracts it. Make sure to check that you don't have discolored spots, fuzz or spores on your carpets or your couch.
As a side note, when you have a flooding in your home then you should always check the carpet and padding regularly.