Ankle pain shooting up calf

Hi! I’m currently training for the Philly marathon, and I’ve kind of paused my training for about a week because of some pain in my right calf.

I have had similar pain before — it started like every time my foot landed there was a twinge of pain up the back of my calf, but in the past, it’s faded if I just took it easy for a bit. This time, it was pretty noticeable after my long run (16-17 mi) and during a 5 miler the day after. The pain got a lot worse the following week, for example if I stepped down in a specific position my knee would buckle, and like going up stairs on my toes caused lots of pain. I just took a week long break from running entirely (I do walk a lot) and I used Biofreeze on it and did lots of rolling. Today I wanted to see how it would feel after a mile, but I couldn’t even make it through the mile without feeling like I was doing more damage… The pain was bad around the outside of the ankle, and shooting up the back of my calf, if anyone has any advice or any idea what this could be, that would be great! Thank you!!