ankle pain

I had reconstructive surgery on the lateral side of my right ankle about 12 years ago.
A few days ago I started getting this wierd pain along the ligament where I had that surgery.
When I flex my ankle I get a crepitus feeling.
It feels like there is “bubble wrap” inside or something fluidy.
It’s not swollen, and it’s not bruised.
And I didn’t twist it at all.
But it’s very uncomfortable to walk on, and I have been icing it and trying to keep off of it as much as possible.
I can tell that something just isn’t quite right.
What could be going on??