What you do now depends on what the flaws in your application were. Hopefully, if there were weaknesses, you've been fixing them all through the application year by adding more experiences, continuing those in progress, taking more classes, considering an MCAT retake, etc.
If you've been rejected anywhere, you might consider calling to make an appointment with a dean and asking what you can do to improve your application. Some need new LORs, some need to rewrite their PS. Some need to practice their interview skills.
It's definitely not to early to start considering what you'll do if you get no acceptances.