How can I face some of these acting setbacks? Serious help please..?

The business isn't going anywhere so relax and be patient. You being 16 means you can do nothing without your parents permission and not being legal means no one in the U.S. can hire you anyway. So your first step really is to secure your citizenship which in turn ensures your legality to work in the U.S. In the meantime, continue taking courses, perhaps take up writing too. There are many other creative endeavors you can engage in while you cool your heels in the professional acting department.