Could it be something bad if I have heel pain?

Treatable. Most of the heel problems are very treatable. See your foot care specialist if problems are limiting your activities. Rest, ice, elevate, limit activity, antiinflammatories and wear a good stiff/stable shoe with good support. Dr l.
Possible. Heel pain is most often caused by plantar fasciitis, a condition that is sometimes also called heel spur syndrome when a spur is present. Heel pain may also be due to other causes, such as infection, tendonitis, arthritis, stress fracture, nerve irritation, retained foreign body, bone tumor, or a cyst. Have it evaluated by a professional and get the appropriate treatment.