IMHO, I don't believe in making bikes fit you to be able to ride them. At 5'8" it fits, you are just not used to it. I believe in alterations for comfort though. In this case you low sided yourself without hitting a fixed object by relying way to much on the rear brake.
It sounds like forward controls may not be for you. That is pretty normal, they are not for everybody. Its a totally different ride.
How bout taking the bike out and unless absolutely needed you use your front brake only until you get used to how it all works. Doing this in light traffic naturally until you get your feet wet and back into the saddle.
Around the neighborhoods reverse that and only use the rear brake until you get the pressure 2nd nature on it.
When I used to teach I found new riders that depend a lot on the rear brake are squeezing the grips so tightly they don't feel comfortable using the levers. At the end of very short rides they would complain that their hands hurt. As they got a lot of miles behind them they would learn to lighten up on the grips.
In any event, glad you survived it with just a bit of pain and damage. I would give what you have more time and practice, practice, practice.
