All I can say is that every one is correct when they say that you need more experience - don't be put off as it can be a really rewarding career, but time, time, time and time is needed.
You also, as suggested, need to find a pro trainer that you can spend time with and watch.
I have had horses for 20 years and I am still learning, in the last 5 years I have re-trained about 40, some of them would have not caused you any problems - even with your age and lack of experience, but a word of warning - I have had a few that would have killed you in about 5 minutes ( and I am NOT joking ) and unless you have the experience you will not be able to see the danger signs until it was too late - it's something that can only come with time.
I am currently re-training one of my neighbours horses - she is a lovely dapple magyar felver, she is intelligent, has an ability to learn and is quick to learn as well, BUT, it has taken 2 weeks just to be able to get her to listen to me and if I move past her shoulder I am asking for trouble - and I know this only because of past experiences. Two weeks ago whilst I was trying to trim her front feet ( no one can go anywhere near her backs ) , she barged me into a fence ( had a huge bruise across my back) and she kicked me in the leg ( I was lame for about a week ) , and that's with me having 20 years experience - so imagine what she would do to someone like you.
As I said DON'T be put off , but seek professional guidance or you will come unstuck ( or worse ) , and no one would want you to be hurt (most of all you )
Good luck and let us all know how you get on.