First you need to ascertain where the pain coming from so bring your knee up to your chest pulling with your hands hold till you get a pulse if it's the lower leg press hard above the ankle bone see if it's painful this is the problem🤔,if the pulsing is above the knee this is a bigger problem.
If it's above the ankle give it a good rub with some pain gell or cream if this won't completely get rid of it but may help.
Otherwise we are talking moxibustion to fix it.