First of all, social services will not take your kids away. Especially when you are seeking help. Google drug dependency charity/care providers. That’s your first step.
Codeine is addictive because the liver turns it into morphine. That’s why you got sick going cold turkey. You need help to come off it comfortably and safely.
In Lancashire there is a drug advisory called Inspire – they have key workers and doctors who specialise in this and can help massively. They will not contact social services. As long as you engage and stick with getting help it will be fine.
My husband was addicted to opiates, then addicted to codeine which replaced opiates. There was never any concern for our kids because he was being treated. That’s the most important bit. You won’t be judged. I’m more worried about the paracetamol to be honest, you risk having a build-up overdose more than anything. You need to find a drug dependency service asap. If you need any more advice just ask and I will try my best. X