My Left Leg, Calf Area Feels Like It Is Swollen

My left leg, calf area feels like it is swollen or tight. I'm a server and after a couple hours it feels this way. I've also been having a twing in middle inside of calf. No sign of bite, no knot. Has been happening for about a month.. when ck leg or foot not swollen. Getting more noticeable and bothersome every day.