How long tendinitis can last weeks to months depending on level of aggravation. But the longer it lasts the more you worry about if the problem might actually be more of a tendonosis than a tendinitis. I wouldn't get worked up about that until you've given it a good 6 weeks of solid rest. That's pretty tough with an ankle unless you learn to walk on your hands.
Sending happy healing vibes your way.
Living life like there's no tomorrow.
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