Premedical Program Rejection

I applied Jan 15. I never received a decision email, but I checked the online portal today to see I got rejected. I guess I'm surprised. I thought my application was good. I went to a top school. My undergrad GPA was good (3.9) and my science GPA was also probably around 3.7. I had taken physics and chemistry in undergrad.

I don't have any clinical or medical volunteer experience. I think this is probably the weakest part of my application. I work in legal aid. I am interested in psychiatry and have taken therapy classes since my undergrad.

I guess I'm a little shocked. My tentative plan is to apply to Columbia's post bacc or enroll in the fall to do a sort of DIY post bacc locally. In the next year, I will volunteer and try to find a job related to medicine. Would it make sense to apply again next year or to other post baccs? Or, should I just try to meet the premed requirements on my own?