What was the diagnosis ? Did x-ray ?
It may be planter fasciitis or calcaneus spur .
For pain relief go for UST and icepack when there is a swelling, when swelling subside go for UST / wax therapy.
Gentle stretching of planter fascia is beneficial.
Also do MFR of foot and sole.
Next Steps
initially take rest , walk less than 25 minutes.
walk with less stride length i.e. steps should be short . use shoe having soft inner sole or it is better to use silicon material / UCBL inside shoe.
Health Tips
shoe modification is necessary.
when you will be okay then follow strengthening exercises for foot and ankle i.e. ankle pump exercise, heel raising , toe crawling etc.
for better result you must go to a good physiotherapist.