There is no distinction between title pawn and title loan. Both are designed to be short term and VERY HIGH INTEREST. It is not surprising you've not made a dent in the principal, that's the way these loans work. Your payments always go to accrued interest first.
The loan shark may or may not allow you to borrow additional on whatever equity remains in your vehicle.
You don't have a leg to stand on.
The only restriction these sharks have is a cap of $125 fee and 300% APR interest.

