Mandy your husband is a selfish, childish arse.
If this your daughter, or a friend, even, if she turned round and said to you, "My husband only allows me X amount to spend on food, he only allows me X amount to spend for the month on everything our child and I need, he knows how little I have, and is happy to buy computer games instead" - would you not hit the roof? Would that not sounds abusive, controlling, neglectful of his resposibilites to you?
He is taking the piss, and needs to grow up. I would put it down purely to his age, but seeing as you have shown him what you have to wear and he said he would think about letting you get more, just says to me is a dick, and would be if he was 22, 52 or 102.
Please, talk to someone in real life. You will hear the same things you have on here, but you need to hear them face-to-face I think to make you realise this is unacceptable and just not normal. Has no one commented on you being unsuitably dressed? I'm not being funny, but surely someone must have mentioned how cold you must be.
You need to have serious words with your so-called husband. You need to tell him that he needs a kick up the arse, and that this is what that is. He is a father, and a husband, and an adult, and he needs to start to acting up to those roles. Video games are not a priority; you having warm clothes so you don't freeze to death is.
Set yourself up your own account, and contact CB - tell them the money needs to go into your account, its circumstances like this it was created for.
I know all this must be horrible to hear, but he is not a nice person. I am two years younger than you, and even the lads I know my age and younger who are fathers know how to budget correctly - and that means clothes for everyone, not clothes and video games for themselves and a bit left over for their other half.
Take care of yourself.