Heel pain needs to be respected. What shoes do you compete in? We always used the hard plastic heel cups that will help distribute forces over the entire rearfoot.
https://www.everythingtrackandfield.com/detail.aspx_Q_ID_E_2696_A_CategoryID_E_272
The rubber heel cups offer less protection IMO as they can be squished to nothing during a big jump but some people prefer those.