What Causes Bloating Of Stomach And Swelling Of Feet?

I am 25 yrs old. My stomach has been bloated and I noticed today that my feet are swollen. At times I have felt that my legs are heavy. I work the night shift so I barely eat or sleep. I am also a single mother with a 7 year old. I stopped working out long ago. But after I had two etopic pregnancies it seems that my weight has been going up not down. What can possibly be the problem. Why do I feel slugish and have no energy.