Without a coach who fully understands high jumping technique (and few do) or a complete understanding yourself, there is no hope of fixing mistakes - none. Good, meaning effective, high jumping technique does not come naturally; in fact, good high jumping technique runs counter to your experience. Experience tells a jumper to dive over the bar in just the same way a child dives up onto his or her bed. That’s what comes naturally, but it is not what makes for an efficient bar crossing in the high jump.
To do it right you must understand the technique and how to instruct your brain to perform what amounts to a gymnastic maneuver. I recommend going to http://www.highjumpcoach.com and reading the High Jump Coach Book on that web site. Then come back here with any questions.