Overweight And Legs Are Swollen. What Could Be The Reason For Gain In Weight?

I want to know i'm overweight right, I have a bariactric bed and my old doctor said to elevate my legs when sleeping. I rearranged my room and now my bed is on the left room and my left leg is gone down from the severe swelling it had, but my right leg is swollen now, but if I move my bed back to the right side of the room my right leg will be smaller than my left leg and it does this everytime. I don't know what else to do . please tell me what to do please. I have a doctor whom I do see 2 times a month and my complete physical said everything is ok. I'm not diabetic, my sugar is fine, my colestral is also normal, only thing is wrong she said is my thyroid she keeps setting me up for an ultrasound on my thyroid but my insurance keeps denying it. so I guess until my insurance does whatever they are suppose to do I can't do what I have to do. Help cause I'm just here lost. I used to weigh 750 lbs about 8 months ago, and now if it wasn't for this one doctor I used to see named Dr. William Eli. Now I weigh 490lbs. but I'm still big. what can I do about my weight now