Heel bone fractures are not so common and usually take place during more serious accidents like car accidents, falls from higher levels to hard surfaces, a significant ankle twisting injury during sports etc.
It sounds more like an injury to soft tissues of the surrounding muscles, tendons and/or connective tissues.
A heel bone fracture would be accompanied by almost intolerable pain
and even taking a brief walk would be unthinkable.
The bruising indicates damaged blood cells deeper beneath the skin in the surrounding area of the injury, not necessarily indicative of fractures.
My opinion is to have it medically evaluated, specially if your symptoms persist or worsen.
Best wishes,
Niko