To determine how many senses humans actually have, you simply need to count how many different sensors there are. For example, the tiny hairs in your inner ear are sound sensors. Seems simple enough. But your ears also have sensors for orientation and balance, as anyone who's gotten dizzy from an ear infection can attest. Your eyes have two different types of light sensors, and your skin has at least five types of sensors, including those for heat, cold, pressure, itch, and pain. Thirst and hunger can also be considered senses.
Some of these sensors work together to create what could be considered one major sense. For example, the balance sensors in your inner ear work with the light sensors in your eyes to tell you where you are in space in a sense known as equilibrioception. Sensors in your skin, joints, and muscles, likewise, work together to create proprioception, or your sense of where your body parts are at any given moment.