You will get more and more experience as long as you keep riding. Riding in shorts tho is definitely not something you should be doing regardless of your gender. It's just not safe because you are at risk of getting clothes caught in your tack, you can pinch yourself or even have problems where you are having them right now.
Proper riding attire is a good place to start, plus continuing with riding lessons. You will learn to ride and follow your horse's motion and you will learn to be one with the horse. Horseback riding was a male dominated sports for hundreds of years, so its clearly a solveable issue or they would not have been riding.