Suggest Treatment For Swelling And Bump In Leg

Hi Doctor, I have pain in my left leg below the knee. I am not sure, whether i hit somewhere like table or some hard object when iam playing with my kid.Its kind of swell or small ball (size is like green peas )or kind of bump . when i touch that place, its moving like a ball. Its been one week i guess i having pain but didnt notice the bump. For the past 2 days i am applying IODEX in that place. I get little pain relief from the pain but still the swell / bump/ ball is there in my leg. Is that any cream or iontment or any compression should i do? or is that anything wrong/ to worry about my leg. I went to hospital but the doctor blindly told i dont know and i dont have any idea about it , lets see after 6 months whether it disappear or it grows . Please reply or suggest me what to do.