ask you doctor for a referral to an nhs podiatrist asap.
This will take a while!
In the meantime see if you can see one privately. There you will be able to buy gel heel supports and also firm supports to wear in your shoes. This will not cost too much, I think my visit cost about sixty pounds for the appointment, gel heels, and slip in shoe supports. If you can wait for the nhs appointment they will make you lovely custom made supports that after you have got used to wearing, you have to wear all the time. You can keep reordering off the nhs as many as you want at a cost of about seventy pounds a pair.
There will be shoes you have to kiss goodbye to, as the supports won't fit in. You will get heel pain if you wear flatties or slippers. Small kitten or wedge type heel will help tip your point of balance onto the ball of your foot and take the pressure off the heel. You must do the same for both feet even if the pain is only in one...
Do the exercises advised on here.
I've had it on and off for about six years, it will get more bearable but may never completely disappear.
I got it from walking miles a day in wellies, which my podiatrist told me off about. I still walk miles a day but now in proper walking boots.
Keep all your boots and shoes properly heeled as soon as you see them getting worn. Good luck and it will improve!