I'm 26 - if I make it in this application cycle, I'll graduate the summer before my 31st birthday. I made some bad, well, not bad, just misguided choices in undergrad. I always was interested in medicine, I just just too afraid of failure to take the leap and do it. So I majored in English Lit - because I knew I couldn't fail at that. I finished my undergrad and got halfway through my masters (in English as well) before I looked up and realized - I didn't want to publish articles, or go to conferences. Hell, I couldn't even pick a focus area!
So, I changed my life - I started taking science courses, I started volunteering at spay and neuter clinics - and I love it! I'm so glad I changed my mind, but I'm also so glad that I got to see what a "bad fit" feels like.
I have to agree with Lunajett - there is something to be said for being a grown-up, having a mortgage, and a car payment, and other bills, and having to manage yourself, and school, and work (because capitalone doesn't care if I need to make good grades - I pay them or I lose my car), and relationships etc. I know myself better now, I understand myself better and I try very hard to remind myself that I am a good candidate - despite having an English degree with a minor in French.
I understand your worry that an adcom won't see those things and will only focus on your GPA - I worry about that a lot. I can only hope that they will look at me as a person - and not as a number between 2 and 4. I also have days when I look at friends I graduated undergrad with - friends who have full time "real" jobs, and vacation days, and real incomes - and I feel like a complete and utter failure - like I'm just playing at this whole vet thing and should stop wasting everyone's time and get a job... But deep down I know that's not the case, and that this is where I need to be.
Besides...I need to look a little older before I bear the title "Doctor" - I still get carded for smokes!!!