You need to find yourself an instructor. If you can afford a horse, you can certainly afford a good solid coach. Sometimes coaches' don't do so well as far as business goes, and they ask for very little money for lessons. Maybe you can go find a good riding stables and work off lessons, that's what I did when I was younger. It's really beneficial for you to have trained help. It's like a young adult trying to fix a car... it would be better for that young adult to have someone help!
Riding is the same. Without help, you can be going down the road of horse cruelty. You could be doing something wrong, and you won't even know it.
There is always a girl who would skip cleaning her room to run outside in the pouring rain in her pj's just so she can muck-out a single stall. <3