Getting shocked like that is a perfectly normal phenomenon in cold and/or dry weather, and particularly in homes with central heat and air.
Static charge build-up is enhanced when the air is dry. So, static problems and effects are often noticed in dry air conditions.The air outside can be very dry when the weather is cold and dry. Indoors, central heating or air conditioning can give very dry conditions which promote static electricity. Heating warms the air and reduces its humidity.
Static shocks are often noticed in cold dry weather, especially when in a centrally heated environment, and may disappear when the weather gets more humid. Static shocks may also be encouraged under air conditioning in hot weather. http://www.electrostatics.net/articles/static_shocks.htm#Does%20the%20weather%20affect%20static%20electricity?