After killing Abel

OK, I'll start from the beginning. A couple of weeks ago I decided to give a sacrifice to god and of course, my brother, Able, decided to copy me and also give a sacrifice to god. I was very upset about this because I thought it was extremely unfair for Able to give a sacrifice after it was completely my idea and he just decided to copy me. So he went along and gave the sacrifice to god and god only noticed his sacrifice and completely ignored mine. This was just completely unfair because it was my idea to do this in the first place! I had to get my revenge somehow, so I planned to kill him. This was only fair because it was so rude of him to do this and I had to let out my anger somehow. So one day, when we were both outside together, I took a rock and hit him in the head with it and he fell on the ground dead. Now, today, the day after I killed him, I feel like I did the wrong thing, and god is ashamed of me. This is not good at all. I let my anger get the best of me instead of thinking it through. Killing my brother was a huge mistake, and I am ready to pay the price for it from god.