Please help me i have a huge family problem!!?

So today we went someplace in the car with my mom, dad, dog, and me. So lately my dad has been extremly mad at me for not rlly being responsible about the dog I promised to take care of. I really hav been trying my best!!!!!! I dont know wat else he wants from me. Well... while my dad was outside buying something outside, my dad told my mom to go check it out. So my mom told me to go with her and my bro was sleeping in the car (and we knew it wud take a second to jst check it out). BTW the store was RIGHT NEXT TO THE CAR, I mean a couple of steps away, and we were outside! So my little brother is sleeping and my dog is in the car. When me and my mom come back in the car since it was cold. The dog clicks the lock on with his paw, and the locks the car. Then we realized that we left the keys in the car!!!! So everyone starts coming by the car and watching. Everyone tries to wake up my brother (but he was soooo deeply sleeping we tried banging the car a billion times that our hands hurt, we shaked the car until it almost fell!!! A whole mob came to help but my stupid brother wouldn't wake up to unlock the doors of the car. My dad starts yelling... cursing alittle bit too. He threatens to "beat my ***" when we get home (even tho he wouldn't). Everyone thinks my brother is dead from all the time that has past and all the oxygen that wasn't left for him. We didn't want to call the cops becuz they would arrest my parents and my parents (even though they can be HUGEEE *****) were gonna cry. I was praying and praying like crazy. I thought as soon as I go home I'm gonna commit suicide. If my brother died it was all my fault. My dad said, "This is the end of that dog!" which meant that the dog I wud die for was going to be taken away from me. I luv dogs I love them so much. So when I got my dog I wud faint I wud do anything. Yet, I don't take care of him that well as my dad says. But I do! He gets plenty of love from me everyday, I feed him fill up his water give him is ointment and medicine (when he needs them) and if I cud walk him out every day I would! But I can't go by myself and my parents are too busy to walk the dog, and so I change the wee wee pad and clean his **** all the time. So my dad always hated the dog, hated him like crazy becuz he is soooo hard to housebreak! He is a shih-tzu (love of my life) but I have tried everything to teach him. He peed on the fancy expensive furniture one day and my dad exploded. He threatens to say, "Either the dog leaves or me" and he says he will have a divorice with my mom. Anyway the dog just ends up being locked up in the kitchen or in his stupid cage. Plus, training school is too expensive and I don't want my parents to spend that money for him. It might not even work. Please I need help! I am in my room right now and soon enough my laptop will be taken away for life. Please answer ASAP!!!!!! I NEED HELP DESPERATELY ON MY FAMILY PROBLEM AND ESPECIALLY ON MY DOG!!!! WAT SHOULD I DO?!?!? IM OUT OF OPTIONS AT THIS POINT!