Started making changes at 27, now I'm 30 and I always need to look back to remember where I started to not lose hope. Weight is about the same in both pictures. Oh and I have Marfan's Syndrome in case you were wondering
It took me until my 50s to stop being self-conscious about my slender body and skinny arms. Exercising more helped a bit but it was mostly in my head. My advice - love yourself now! (The sign was for a Twitter pro-nudity campaign)