I also have a degree in Psych. I am currently in my second year of an ADN program. I have to say I WISH that I became a CNA and had other experience before I entered the program. It could have helped me with my anxiousness and apprehension when I first began. I was shell-shocked after not having this depth of medical experience.
I think you have the right idea. Becoming a CNA will give you insight into what you have to look forward to and helps get you in place to start collaborating with doctors and/or nurses.
I worked as a Direct Care Worker for nearly five years but that position has nothing on the work of being a CNA and learning how to become a proficient, competent RN.
There are different CNA programs which vary in length in the metro Detroit area. I believe there is a program offered by the State (statewide) which entitles you to your money back for the training as well as the testing fees after you complete and have secured a job as a CNA, if you are within a certain income level. Sorry don't know the name off hand of the particular place

You'd have to search for that one unless someone on here knows.
Another idea is you can wait until you finish Foundations of Nursing and apply for the exemption and just take the test. But since your not yet admitted I'd say take whatever CNA course which usually ranges btwn 3-12 wks depending and get started.
Good luck!