experiencing really bad aching pains in my lower legs

hi. i am 20 years old and i experience really bad aching pains in my lower legs at night i sometimes get cramp which is really pain full. this pain keeps me awake all night as i have to twist and turn to make myself stop focusing on the aching pain. i do tend to have cold feet but my feet have always been colder than my legs, i dont know is this is to do with bad circulation, i also have some bruises on my legs i believe this is due to the pain as i have had no trauma to them. i dont do vigorous excersises or wear high heels, i dont know what it is, but the pain keeps me awake all night.