Hi,
Thank you for writing to me and for telling me how you're feeling about your home life. It does sound like you are living somewhere that is causing you a lot of distress, and I'm sorry to hear that your mum thinks you are over reacting. There certainly seems to be a lack of space, and there also seems to be a risk of you coming to harm. However, you do seem to be aware of the risks to your life if things don't improve, and you write that you don't want things to stay the same as they are anymore. All these feelings can make you feel like running away, so it is not surprising that you have already tried that, but as you found out, it didn't make anything better.
It may be possible for your family to get some help with things at home, and social workers can help to organise both practical and emotional help for you. It can be a bit scary though, trying to get help when you don't know anything about social services or how to contact them. A ChildLine counsellor would be able to explain to you how they could help, and even help you make contact with a social worker, if that is what you decide to do. Call ChildLine on freephone 0800 1111, or sign up for a ChildLine account and click the online chat to have a conversation with a ChildLine counsellor online.
Take care
Sam