Brianne, if you are for real, and this has happened to you (sometimes we get trolls who make up stories), then I am very, very sorry. I know what you are going through seems unbearable. But you have to forgive yourself. You did everything you could to give this baby a chance at life and if you accidentally lay on her, then it was just that — an accident. I do not think you can be sure that it was that that killed her. Tiny kittens are very fragile and if she had been ill treated by being thrown onto the concrete, as you describe, I think it is very likely that she had brain damage or internal injuries that might have killed her. All of us who have tried to save kittens have had disasters and have lost them, kittens before the age of four weeks who lose their mums are terribly hard to raise; they die for all sorts of reasons and it’s quite likely she died of natural reasons — even without having been injured first, the death rate for abandoned unweaned kittens is very very high, around 40%. There is no way of knowing whether your little one would have made it, even without this terrible accident.
You are only fifteen. But you have a great heart. You need to keep on going because the world needs more people like you who care about and try to help animals. I know you will go on to help many more animals because you obviously love them and we need people like you to help stop people like those horrid children who hurt the kittens, and to rescue the little ones. Sometimes terrible accidents happen: people’s kittens get outside accidentally and run over, sometimes in the garage or driveway, they climb into washing machines without getting noticed and drown, they are curious little things and the world is full of dangers for them. Please don’t ever ever think about hurting yourself, the animals need you for all the good you will do in your life for them, everyone makes mistakes. Talk to your mum about how you are feeling or your doctor, ring Samaritans or a helpline, please get some support. Mamas would forgive you, she knows you loved her and tried to help her, we who love cats forgive you too.