How do you know if you have a disease?

How do you know if you have a disease?

See a doctor if you experience any of the following symptoms: Muscle pains and body aches that are persistent, or that come and go often. Numbness, tingling (pins and needles sensation) or discomfort in the hands, feet, or limbs. Pain, tenderness, stiffness, swelling, inflammation, or redness in or around joints.