I Think I Might Have Pitting Edema? The Only Area

I think I might have pitting edema? The only area that pits is my shins, not my ankles, or feet. I am pretty overweight, but have recently started a new weightloss treatment that cuts out a lot of sodium and such, and I noticed after a month it has gone down, but it's still there slightly. I fear it might be congestive heart failure, but when I signed up for the weightloss program, they did an EKG, and my heart was fine, even for my weight. I haven't really tested to see if it happens in the morning, and my job does require me to be on my feet 5-8 hours without a single break so I wonder if it's actually edema, or swelling.