Worried about swelling...😐

Sarina💋 • I'm 25 • FTM • I gave birth 3 weeks early to an amazing little boy named Cameron • 10/6/15 • 7lbs 8oz • 20in
When should swelling be a concern? 35 weeks and my feet and legs seem to get the worst of it. I feel like I'm walking on water balloons. It's been going on for about 2 weeks now. I stay hydrated and elevate my feet when I can. I'm wondering if I'm taking in more water then my body is putting out. What should I do?