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.
Symptoms of otitis externa. Otitis externa can cause a number of different symptoms affecting the ear and the surrounding area. Symptoms can include: ear pain. itching and irritation in and around your ear canal. redness and swelling of your outer ear and ear canal. a feeling of pressure and fullness inside your ear.