Yo ask if you have experience of addiction?

I am not trying to be blunt but honestly, even if a GP did "judge" you when you tell them about this addiction, it's a lot better to get help and get off the painkillers than it is to allow the addiction to grow.

Four months at low-level doses is at the lower end of painkiller addiction. The GP probably won't judge you, most are too professional. But the most important thing is getting help now while you still can.

Addiction usually ends in two ways, the user gets treatment and works themselves off the drug, or their addiction spirals until it kills them. The sooner you get treatment the better chance you have of getting clean.

Nobody starts taking opioids or opiates with the intention of getting addicted. The addiction sneaks up on them. Most are in very deep by the time they realise.

A big positive for you is that if you think you are addicted at this early stage, you quite probably aren't. You might be in the habit of taking the drugs and enjoy the feeling, but that's not the same as being chemically addicted. The big sign of an addiction is you increasing the dosage or taking stronger substances. Sticking at the recommended dose, albeit for longer than the 3 days you're meant to, is actually a good sign for you.

(I know it's not the same but I thought I was addicted to soluble paracetamol. I took 8 tablets a day for 20 years and had headaches if I didn't. My doctor told me to stop, and I was able to stop. I had a headache for a week and since then almost never get a headache. I wasn't properly addicted in a chemical sense, it was just a pattern of behaviour that I didn't see as a problem until a doctor told me it was. Even though it was bloody obvious to a normal person it was a problem to be taking painkillers every day for two decades - I needed to be told!)

You probably won't have developed a serious dependency at low levels over 4 months. However you are absolutely right in seeing your enjoyment of the warm fuzzies as a red flag for addiction (a different thing to physical dependency). Some people metabolise codeine in a similar way to the heavy duty opiates like heroin and those warm fuzzies are the sign you're one of them. My strong advice is to step away from codeine, now and for good. It's a very slippery slope to dependency and the other drugs that tend to be mixed with it on prescription and OTC, ibuprofen and/or paracetamol can cause very serious health problems at the levels you end up taking to get your codeine fix. If you struggle with physical withdrawal then google codeine tapering plans.

The dosage is irrelevant. If you've been taking them for four months because you like the way they make you feel, rather than because you have a chronic pain condition that requires treating, then you have an addiction.

You won't know if you'll get withdrawal symptoms until you actually stop taking them. My guess is that you probably won't, especially if you cut down gradually. But you can definitely get advice from your GP. They won't judge you. And even if they did it wouldn't matter: their opinion of you is irrelevant and they are obliged to provide you with appropriate advice/treatment whether they approve of you or not.

What dose of codeine in the Cocodamol, is it higher( ie prescribed) or Solpadeine Max ( over the counter)? How many tablets are you taking in any one 24hr period?

I have experience of addiction (cigarettes) but not of opioids.
However, my experience of addiction is that your addiction hijacks the "reasoning" centre in your brain and you find many excuses to keep consuming.

Yesterday, I had a whole conversation with myself as to why it would have been not only reasonable but even preferable to go out at 9pm to go buy cigarettes, according to my brain, my entire life would have been improved, there was a whole argument, point by point, all seemingly perfectly valid.

Obviously I didn't do anything, but this is how addiction looks like.

I believe your fear of being judged by your GP is one of those arguments.

Please see your GP. Forget judgement. You won't be the first and you won't be the last person they see with this problem.

they'd much rather try to help you than see you die. A good friend's daughter of mine died just shy of her 30th birthday from this 😢

GPs are there to manage your health. Is being judged really worse than damaging your health with potential addiction to opioids? Not in my books.
Nobody has ever died from someone judging them in the privacy of their own head. Plenty of people died from opioid addiction though...

You need to contact your GP and they will be able to offer you a safe titration plan so you can come off them gradually and under medical supervision. Don't suffer in silence as the longer you leave it, the more difficult it will become to stop.