I thought about your problem for a long time then. First let me say that you were very smart to lie down when your Mom put the harness on you. I would fight and kick and run away. You have to always remind people who is the boss. They tend to forget .
People have very short memories.
I am sorry to tell you, but I agree with your Mom here. If you could get too excited and accidentally jump off the balcony you could kill yourself. I know that I am always running and jumping and climbing and sometimes I slip. If it can happen to me, it can happen to anyone. It is my duty to give you the best advice I can, and my advice in your case is to forget about going onto the balcony.