As per your explanation for self check, You can try to hold the muscle belly of your left leg calf muscle and squeeze it. If the muscle is pain full then it shows it can be related to atherosclerosis (clotting) in your blood vessels under the muscles. Another test is sit in straight leg position press your knee down and stretch the feet towards you. It some one can help to stretch then it will be better. And again you have to see if there is pain then the test is positive and there might be a problem with vascularity for the affected leg. Here the test will give suspected result how ever the conformation can be done with dopler test so you may need to go for it when above two test are positive. And then visit a vascular doctor who can suggest you medication based on the result. Now when the physical test are negative means no pain with stretching or squeezing calf muscle means there might be weakness or soreness of muscle. In this case you should use hot pack or deep your leg in hot water with added salt, you can also use cold pack to reduce inflammation. Do this for 2to 3 times a day and check. You can also take help of physiotherapy treatment like ultrasound and few stretching exercise as well if needed analgesics for time being. I also suggest once do check your blood pressure and sugar level too. Take care.