There are several varieties of foot conditions that may instigate heel pain. Excessive standing or walking are normal sources for foot and heel pain. To treat mild to moderate heel discomfort, rest and ice will reduce the inflammation and aching. Replacing old shoes or improperly fitting shoes with new ones, and the use of shoe inserts, can also improve heel pain dramatically. If discomfort continues to persist, try an over the counter NSAID like ibuprofen.
If the heel pain is severe enough to interfere with your daily activities and includes symptoms other than discomfort, it is possible that there is an underlying condition contributing to the pain. Such conditions may include Achilles Tendonitis, Plantar Fasciitis, or heel spurs. You should see a doctor immediately if your symptoms include:
Swelling near the heel with severe pain
Inability to bend the foot downward
Heel pain, numbness, or tingling, along with a fever
An injury followed by severe heel pain
While you can speculate which condition you may have, it is best to get it looked at by a doctor who can give you a clear-cut diagnosis with treatment instructions. Self-treatment without a diagnosis could result in further injury.