Strained/sprained my good ankle

I just rehabbed a mild-ish sprain (took about two months) that occurred on uneven snow.

…and now strained the other (good) one yesterday! No roll, no rough terrain, nothing. Just sore, a little tender, and mild pain when in certain positions.

I am 40+ and have taken a long break from running, but never had these issues before. Would love thoughts on what’s going on.

My only plan at this point is to rest and strengthen both ankles with PT exercises, but I’m so frustrated!