I went from taking 20 mg to 40 mg of simvastatin 5 months ago. My legs, specially my calves, have become super weak. I get very thirsty, specially, at night. I urinate a small amount 5 or 6 times, also at night. I have trouble breating after walking 10 to 20 yards. Finally, my eyes water and my vision is somewhat blurry. Thank you.