Sounds more like an Achilles tendon tear.
If you heard a crack, I would go to the doctor for an X ray. I am not one to go to the doctor either.
Good luck.
Plantar facia...and most of us that have been into cycling and are older have had this.
What cured my feet issues and I have had my share.
- Rigid sole carbon shoe with ample toe box
- correct foot bed matching arch or custom orthotics
- moved spindle back about 10mm behind ball of foot which reduces stress on Achilles.