Try 27 and you've just finished growing your hair out for 5 years. My ponytail tied back doesn't always cover the receding points. That's how I found out how much it has had receded actually.
Bought minoxodil 2 weeks ago and started using it... shedding more hair now... but I think I'll shed more now while i've got it to shed and long hair and if it's going to help in the long run. I might as well start now... £60 a years supply... I'm sure it cost £500+ a year before the internet. It's not even suppose to be good for frontal receding... so I'm actively looking for something else so I can save my front hairline. I don't think I will go as far as transplants as a band transplant can leave scars even if you go bald after.
My father started balding at 28. I asked him this many years ago in my early 20s so I knew it was coming... Didn't think it would affect me the way it is, but that conversation was enough to say fuck it... I can grow it for now because when I'm older I wont have a chance to.
Anyway all my friends suggest fighting it being stupid, shallow, etc... I just haven't told them I'm using it. But all those fighting balding in their 30s say they wish they started sooner and they might have had an extra inch on their hairline. It's easy to say don't use it if you're not gonna bald until your 40-50s. It's easy to take the piss when your young, but you know what... I don't think many people give me great advice anyway, it's more likely people would want me to bald. The same reason I work out... I want to maintain my mental sharpness into 30s-50s because those gifted with 150IQs who let themselves go are gonna be in for a shock as they get older, your looks are going to count for something, and realising that it is and people are shallow is part of the battle. Life ain't fair.
I am grateful I am not the 5'3 person who was fat and balding age 16 at my secondary school. He looked 16 going on 45.