How much should I worry about lower leg swelling?

Lower leg swelling. Lower leg swelling can be due to a variety of conditions. In addition to musculoskeletal causes, it can be due to cardiovascular and other medical conditions.; medications for high blood pressure can cause it, for example. You didn't indicate whether one or both legs are swollen, nor how long the condtion has lasted. I would recommend seeing your physician to have it checked out.
Depends on whose leg. If its your leg then it is appropriate to be concerned. However, leg swelling can happen for many reasons. Heart conditions, kidney problems, vein or artery disease, or local injury or arthritis, infection, and others. If you're concerned it is always best to see our doctor.