Hey there Adam, Im glad i saw you post,
I found myself in a similar situation around your age, I am now a 24 year old freelance web entrepreneur with clients of my own and collaborate with businesses.
I found myself with little choice of places to go study and decided not to give up on my dream, so I learned coding from websites like w3schools, php.net, youtube and other places, It took me a while because I had a day Job till I was 22, but I guess, what I am trying to say is, that If you are really sure that is what you want to do and are willing to "get out of your way" to make your dream a reality, it really all comes running to you, and almost seems effortless.
I hope this message can inspire you in some way, if you think university is your way, then do it, but its not "necessary", it all comes down to your own willpower.
Good luck, Ben