Gaining Weight While Breastfeeding

I am 5'2 and weighed 130 pre pregnancy, I gained 30 during pregnancy putting me at 160. I lost 15 of it right away putting me at 145 and then lost another 5 putting me at 140 at about a month post partum. And I have gained back 7 pounds so I'm now back to 147. This is all just within 6 weeks. I don't understand what's going on but this extra 15 pounds is VERY noticeable a girl my height and I'm very self conscious and getting very depressed by it. My stomach is now sticking out almost like it looked when I was 9 months pregnant and it just doesn't make any sense to me. I'm eating healthy, drinking tons of water, and doing light excercises. Every time I look into the mirror I cry especially after I shower and have to look at myself. Anyone going through the same thing or have before and may know what's wrong with me?