Hi and welcome. I am sorry that you are experiencing these problems right now. We can sometimes get overwhelmed with worry when something physical triggers anxiety. It is a common occurance, and hopefully once you get the answers you seek, it will go away.
It sounds to me like there is a likely physical cause to what you are feeling in your legs. Have you tried seeing a sports therapist? I am wondering if this could be a sports injury/overuse issue?
I think that you need to find the cause of your symptoms, get it treated and hopefully then your anxiety will fade naturally.
If you find that it doesn't, then post back and we will do our best to help you with health anxiety issues, recommendations and support:)
"Courage is not the abscence of fear, it is feeling afraid and doing it anyway!"
"It is when we are most lost that we sometimes find our truest friends"
Panic Syndrome recovery due to CBT