Edema with Continuous Diziness.

Hello Dr, Please Help me... Since a month, i am experiencing symptoms of  edema on legs, feet, somewhat on hands and somewhat on face. This edema occurs when i sit or stand idle just even for 10 mins, legs start to swell and dizziness comes. When i elevate my legs and sleep the edema gradually goes and dizziness also goes. I went to dr. He did 2D Echo, Serum Albumin, Serum Creatinine, BUN, Serum Albumin, Serology. All the reports are absolutely normal. NT Pro BNP. 2D ECHO -  LVEF : 60%. NT Pro BNP was initially 27, 89 and 102 when last tested. Should i test NT Pro BNP again? What will be the reason of my edema and dizziness/lightheadedness? Please help. Am i going to die soon? Am i having any hidden heart failure? Any other test should i do to evaluate the heart's condition?