Not lost any weight?!

I gained 55lbs during the course of my pregnancy, I had my son and my stomach shrunk considerably. I thought I had to of at least lost 30lbs, stepped on the scale, and nope still the same. My legs are extremely swollen so could that be why?! So confused that after having an 8lb 11oz baby how my weight wouldn't drop down...at least that amount. Haha, probably should have waited at least a month before trying to step on the scale.