Decline for and reapply next year? I applied to a professional program that I had been striving for in my undergrad, at a top school, but I've since felt overwhelmed with how to pay for it and incurring so much debt. I think I should wait a year so get into a better place financially. I've become so anxious, thinking I've ruined my opportunity with this school if I don't go.

I am considering withdrawing my application, but I'm very worried about how it might hurt me in the future when I reapply. Or I may wait but need to decline if I am accepted, and reapply the following year. I feel like both will hurt my chances in the future. How will admissions consider me the second time?
I would wait until you know the outcome first. It is possible (and not that usual from what I hear) to defer an offer of admission, which means you may be able to take up an offered position in the following academic year.

Since you do not know that you have been admitted yet, I would wait until you get a response. If you are rejected, there is no harm in re-applying next year. If you are offered a place, a request for deferral will not be looked upon badly.