I have this problem and have even torn one of mine as well.

Treatment is rest, ICE and stretching. The best 2 I do is on a stair (or raised platform) and lower your heel using your body weight to slowly give it a deep stretch.

Next one works best with gym shoes. Put the ball of your foot on the wall, heel on the floor and bend you knee pushing your hips into the stretch.

I recommend Tumeric, I take it everyday and it has worked really well and you can get off the Advil once it builds up in your system.

Doctor is a good idea but if you have it, they will likely tell you something pretty close to what I just did.

Avoid running or any sport with hard stops like basketball or tennis, at least until the pain is under control...it will just aggravate the injury and it will never get better.
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