Retail "therapy"?

Usually I love to shop, afterall, coming home with a cute new outfit will boost confidence and make you feel good about yourself. Walking into the store today, I was excited to find a new outfit for the summer. Then I noticed that every single person in the store was skinnier than myself. Everyone was prettier. This made the items I'd typically want to buy or wear so ugly. I was with my mamabear and that didn't help me feeling self-conscience at all. A couple of weeks ago, I would not have cared. In fact, I would have probably had less options because of sizes being too big. A couple of weeks ago I had lost weight. Now, I can tell you I've gained 8 pounds. I know that seems like no big deal. But for me, it goes straight to the back of my hips and makes me look pregnant. The places that make shirts and pants look like shit and not fit. So now I want to lose pounds to change that and look the way I'm supposed to and what I am used to seeing and what is my normal weight. I want to do this because one of my biggest fears is being overweight and at the store, having to get jeans that were 2 sizes too big, and in my eyes that is leaning towards being overweight. Now I am so anxious and I feel so self conscious and disgusting. And when my mom kept telling me "no you haven't gained weight," "you look fine," "if you don't get that I will be so mad" it made me feel so much worse about myself. I know I'm just being a stupid girl about this, but it's my fear.