I cracked my iPhone 6 screen?

So, basically I was at the park and my parents always tell me to put on my otter box case but I can't find one of the pieces of the case there are three pieces. There's the piece with rubber on it and two plastic pieces. So I was in the park talking to my friends sitting on a bench when all of a sudden after talking to them for 5 minutes not even moving, my phone just falls out and from a foot off the ground my phone screen just shatters! I was so angry because every time something I get breaks it's not my fault like last time! But it's too long to explain there's only 921 characters left. So, anyway, my mom happens to walk up and I show her my phone because this time it was a little on me and I admitted to my mistake and my friends told her what happened and my mom said well you could have at least put on the two plastic parts! I said that's one of the parts I was missing and she knew that I lost my case and we were supposed to buy a new one last week but something came up. Please help and thank you for reading. Also sorry for all the grammar mistakes

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