There is no caffeine in the 30/500's of co-codamol and in the UK it is only available on prescription.
The strongest amount of codeine you can buy is 8mg and it is in combination with paracetamol and ibuprofen.
Tyelenol is the brand name for paracetamol in the USA, and there are combinations known as T1, T2 and T3.
In pain management codeine is addictive. but things like ibuprofen, paracetamol, diclofenic are not.
What you are doing is trying to find ways of keeping your codeine levels up to get rid of the withdrawals. And yes the sypmtoms you say sound like withdrawal from codeine.
There is a site in the UK called 'codeine no more' I think. Something like that and they offer help to people in the UK.
They also have a guide to help you taper off from codeine.
A taper is a plan to reduce the amount of codeine you are taking and avoid the withdrawals.
I would have thought that you were banned from other sites for talking about how to get more codeine.
I know you did not mean to do that and probably the best way forward is just to forget about it.
I hope this makes things a bit clearer.
xx