re: Advice for a 20 year old - warning tl;dr

I've said this before, but I would just do my best to avoid debt. Pay off the credit card every month and avoid student loans, and you will be doing better than at least 75% of other students.

The thing that would most help your retirement would be to finish your undergraduate degree on time (four years) and get into PT school immediately, avoiding getting put on the waiting list for a year, which basically gives you another year of earnings before retirement.

Probably the most important thing for maximizing lifetime earning potential would be to get into LSU's physical therapy school. You're going to need loans for PT school and payback on loans for LSU PT school is a hell of a lot cheaper than a private school like St. Augustine.

Use the extra 50-100 bucks a month you have now to have fun, take road trips, etc.