The cause of muscle cramps isn't always known. Muscle cramps may be brought on by many conditions or activities, such as: 1  Exercising, injury, or overuse of muscles. 2  Pregnancy. 3  Cramps may occur because of decreased amounts of minerals, such as calcium and magnesium, especially in the later months of pregnancy.
Putting fingers, cotton swabs or other objects in your ears also can lead to swimmer's ear by damaging the thin layer of skin lining your ear canal. Swimmer's ear is also known as otitis externa. The most common cause of this infection is bacteria invading the skin inside your ear canal. Usually you can treat swimmer's ear with eardrops. Prompt treatment can help prevent complications and more-serious infections.
Conditions that Cause Outer Ear Pain. Otitis externa is the medical term for swimmer's ear. Swimmer's ear is an infection of the outer ear caused by contaminated water. It is common among swimmers but can also occur when the ears do not completely dry out after baths or showers.