I've been in this boat, so maybe I can help a bit.
I went to a university for about three months before ultimately deciding to leave to pursue a job offer at a company I had applied to. I didn't actually end up going to that company because it was in San Francisco and I wanted to stay in my home state, but I did get a matching offer from the employer I had been with prior to leaving for school. It has been a year since then and it has been incredible and exciting but there certainly are downsides to choosing this lifestyle.
1. It is exhausting. I went through high school without exerting very much effort and the most challenging experiences I had were my job outside of school or related a girl or some other social drama. However, at the time it was very clear between me and my employer that I was still in high school and that it came first so I always had an excuse if I needed a break or just some time relax or cool off. Once I had signed my full-time employment contract that understanding was thrown off a very tall building and then shattered under the pressure of an immense amount of work.
I was in no way prepared for as much stress or exhaustion as I endured at that job, and it was one of the biggest factors that led to me quitting. I'm sure freelancing has been stressful, but it's worth considering that you will not be prepared for the amount of stress that you will have to deal with if you choose this path either.
Since leaving that job and taking another position at a startup, I have been incredibly happier. But guess what? That stress does not go away. I am able to manage it much better these days, but it took a long time for me to get to where I am now.
2. It is lonely. To be fair, I am not the most social or outgoing person, and maybe you're better at meeting new people, but this can be a numbingly difficult problem to manage. I've lived alone for almost a year, and I've grown to love it. Making and enforcing my own rules makes maintaining my lifestyle (ex. long hours, late nights, a lot of sleeping on the weekends) much easier. But outside of work, I don't spend a whole lot of time with other people. On weekdays, I generally get home late enough that I am too tired to do anything else, let alone make an active effort at maintaining multiple personal relationships. That being said, I still find time to see my (established) friends on the weekends and holidays (many of which go to school locally so I am immensely lucky in that regard); however, it isn't really enough to combat the loneliness, not to mention it can be quite the tiring endeavor. The nicest thing about college for me was just being around people, specially people who are my age. You will be the minority in the working world and that can be really terrifying and intimidating when you don't have others in similar positions surrounding you. In school, you can be afraid or worried or intimated but it doesn't matter because most of the people there probably are, too. And this quickly fades as it is far easier to get comfortable in an environment where you are part of the majority. College makes it easy to be social, whether you accept it or not. In the real world, where most people aren't going to be your age, you have to work several times harder to experience an even remotely similar level or intensity of social interaction. There are more details to this that I don't necessarily won't to speak about publicly, but I'd be happy to talk to you about it over email :)
...continued in the linked gist.
Edit: added the 'continued' bit.