What Causes Pain In Legs And Hips In The Mornings?

LEG AND KNEE PAIN AT NIGHT LEFT LEG HAVE TO LIE ON MY BACK THEN ITS NOT TOO BAD IN THE MORNING IT FEEL LIKE MY LEG IN ACHING AND HIP ACHES FOR FEW HOURS. THEN ITS STARTS AGAIN WHEN I GO TO BED . I AM FEMALE OVER WEIGHT APPROX 25 LBS WHICH AM TRYING HARD TO LOOSE TAKE THYRIOD TABS 75MGS HOPE YOU CAN HELP PLEASE LINDA UK