Major identity crisis

I know this is probably the stupidest thing to complain about but it is a serious issue for me right now. I am having an identity crisis. I have no idea who I am anymore. I have focused on losing weight so completely that I haven't been very focused on anything else. Everything about me is changing. Of course my body has shrunk considerably but I am changing on the inside as well. I used to believe that shopping for clothes would be easier and more fun when I had lost weight. It is so much harder to clothes shop right now than it has ever been in my life. I go shopping and naturally migrate to the Plus size section. Nothing in that section fits me anymore. I look at the clothes in the normal size section and I feel like a fraud. I feel like I have no business in that section and fully expect one of the employees to come and tell me that I can't shop in that section, that I must shop in the Plus section. I sometimes worry that I used to be nicer than I am now. I am not a jerk but I used to not speak up for myself. I used to feel like a floor mat for other people. Now I don't take it because I deserve better but, I worry that it makes me come off as a jerk. I am so confused. I have no idea who I am, body or mind, anymore.