This subject I have a fair bit of experience with... Here are the rules:
1, in order to get financial aid, you need to be degree seeking
2, if you have a degree, you can only take 60 credits without being granted a second bachelors before they cut off your financial aid (please be aware of this, you cannot take endless courses on financial aid) and there is a max for your first degree as well...
3, your grad and undergrad loans are different, you are thinking of lifetime maximums, where they all count together.
4, you can only be either taking classes as a Grad or undergrad student, never both
5, it COMPLETELY depends on the school or school system. In MN (where I live) the University of MN system (UMN, UMN Duluth, etc) does NOT grant any financial aid for seeking a second bachelors degree, not in any circumstances, best they'll do is give you one year to complete prereqs... However, the Minnesota University and College system (St. Cloud State, Winona State, Etc) will give you financial aid until you get a second degree or reach the max post-bacc credits. You could get 10 degrees and they'd keep giving you another 60 credits after each degree...
6, you need to be at least PT or 6 credits to qualify for federal financial aid
Hope this helps, and good luck!