My knees crack and pop everytime I squat down, is this normal?

Common, not normal. Knees cracking and clicking (crepitus) when squaring down is a common condition, but not necessarily normal. Most commonly this crepitus is due to roughness to the cartilage behind the knee cap. Treatment involves maintaining range of motion, ice, anti-inflammatory medications, and knee strengthening exercises. Persistent pain should be evaluated by your doctor.
Not normal. The cracking is usually related to the tracking of the kneecap. The kneecap joint can be irritated, or, it may be arthritic. See on orthopedic knee specialist for an exact diagnosis.