Never be skinny

So me and most and of my friends and any other girls I know really want to be thin but it's just not happening I have said it for a few years and recently I decided to try and start been active so I joined the local gym but don't really know what I'm doing there I just run until I feel like I'm going to pass out!
I got a personal trainer session and you could tell that worked because I was aching and I recently joined up to a morning bootcamp three days a week aswell I havent lost any weight as of yet as it seems impossible to do! As I LOVE food I just purchased a tea detox where you drink tea for two weeks and eat healthy has anyone else ever done anything like this or any good weight loss tips :)! There are some before and after shots of people who have done the detox I'm unsure !!