Growing up? No Thank-you!

As we get older there are many social norms that are thrusted upon us. There is a society-imposed biological clock that begins to tick at 20. Graduate, get married, have babies, game-over. Seeing as I'm in my early 20s, people say "oh, you're so young, you have so much time to have fun and enjoy", but in reality I feel as though time is of the essence. I am still constantly dating the wrong people and telling myself that I can start bringing up my grades next semester. Your twenties is supposed to be filled with good-times and life-long memories, but realistically speaking if you fuck them up you're in trouble. I still have yet to meet a boy who doesn't view sex as a conquest nor have I completely narrowed down my career path. In the past going to university guaranteed you a good job and a stable life, now university could be just as useless as not going. The program I want to apply after my BA requires not only amazing grades it also requires absurd amounts of volunteering, experience in the field, being a well-rounded person, and of course not to mention being able to stand out among thousands of other people who want it just as badly as I do. Stress washes over as I realize that every academic movie I make from here on end can potentially sabotages my entire future, THE REST OF MY LIFE. Along with having my life figured out I am also supposed to "date the right people" so that I can prepare myself for the stage in my life where I am supposed to close myself off to every man in the universe except for one. This is all fine and dandy but if I am trying to compete against thousands of other candidates for a spot in this specific program, thus studying a shit load, how do I keep myself from turning into a social pariah? There is no answer here. I don't exactly agree with the whole "trying to find a life companion thing", but after living in the society that I do getting married in your late twenties or MAX early thirties is the only acceptable norm.  If this doesn't happen not only will my family be severely disappointed, I will too , in a weird twisted way. If I am working my ass off to finish school and obtain a fancy degree in a fancy program, what is the point if I can't share that with someone. After all our one and only sole purpose on this planet is to procreate. The worst part is, as a young adult I have become accustomed to coming off as completely put together, so has the rest of my generation. Therefore we are all walking around like we have out shit together, because one HAS to have picked a major and have plans for the future by the time they reach this age. This puts stress on themselves and on other people who are lying and embellishing the truth about the same things because they think everyone else is so established. This is a vicious circle. I know I am not the only one confused and terrified that adulthood is around he corner, but I can't express these fears because everyone is so good at hiding their own concerns.