Hmm after thinkibg about it, it seems my parents somehow fucked me up, by making me always trying to prove myself to be good enough. In time its become an intuitive process and is applied to every situatuon i face... How sad. You other 19 year olds are lucky to be free of mental chains.
College is like training wheels for life. You're given enough freedom to feel independent, but there are still safety nets all over. What are you trying to prove? Good enough for what? Are you trying to prove you're worthy of love? If so, maybe you need some confirmation that your parents love you. Chances are very high that they love you more than their own lives. That's probably why they push you to accomplish so much. Parents always have an idea of what their child's ideal life looks like and often try to make that a reality whether or not the child wants it. The trick is learning to be content with who you are while striving to improve. If you are trying to be good enough in every situation, that's fine. But if you fail, that's OK. You're not out of the race. I don't know if it's an INTP thing, but I know I fear failure. It's something I have to work to overcome. That's all part of becoming an adult. You discover you have flaws, you take responsibility for them and try to improve.
As far as how to act...It honestly depends on who you are around and how you want to be perceived. No one ever outgrown immaturity. Just ask any married couple. Immaturity is essentially selfishness. The immature person does not care for the feelings of others.
At 19 you should probably develop a plan for your life. You're not stuck to it, but it's good to have a direction and goals. Once you have that, screwing around making youtube videos isn't that big of deal. If that's all you want to do with absolutely no plan for the future, then that's a problem. You will be limiting your future options. Personally, I hate plans. They make me feel trapped. But if I think about them as tools to give me more options in the future, they become much more manageable.
Growing up is hard, so I'll leave you with this: