You've lost your contact by dropping your hands. Also, your shoulders are rounded.
You are ahead of your horse. You need to sit back, wait with your horse, and let her bring you up.
Jumping ahead has several causes.
The rider is trying to "help" their horse and jump it for them.
They are defensive and are trying to get a good distance.
Your position looks a little defensive to me. Be confident! You are taking your horse, your horse is not taking you! (:
You need to open your shoulders, sit back, and wait. Just wait. Your horse will bring you up. When you tip forward like that, you are putting too much weight on the forehand and making it harder for her to jump. You need to make sure you are not interfering with the jump process.
Also, keep jumping cross rails. It looks like you are off to the right side of the jump. Make sure you jump in the middle. Cross rails are a good way to practice jumping in the middle.
distances are like men. never grab the first one you see; it's never the best one, more will come along.