Left calf pain

So for about just over a year now I’ve been experiencing bouts of calf pain. It’ll usually start up after I’ve been sitting for a bit and it’s usually in the back or sides of my left calf. The pain really hurts and also freaks me out. I’ve been checked for pod clots and nothing was found. The pain will sometimes travel to my ankle, bottom of my foot, behind my knee, and sometimes to my butt cheek. Once in a hole it will turn into a Charlie horse but that mainly in the night. Im still super paranoid about blood clots but I have no idea what this is. Has anyone else experienced anything like this?