Can I get in trouble after I filed a false elder abuse report?

Yes, you can be arrested and charged with a crime, possibly multiple crimes depending on how you reported the false event and to whom. Considering the falsely-accused person has been arrested, you are probably better off exonerating this person sooner rather than later. If your attorney knows about this, I'm not sure why you are consulting this forum instead of him. I'm sure he has more details than what you wrote on here.