Stretch marks

So one day I'm on the toilet and I notice... stretch marks... I wondered how but I noticed how I've been eating more and exercising less. They started on the side of my legs and on my butt but they have spread everywhere and now between my legs 😔 I feel ashamed and want to punish myself somehow, I'm disappointed in myself. I can't find confidence in myself and I'm embarrassed and I don't know what to do 😫