This sounds so much like me..except my pain is in a different area to yours. I am going to be honest rather than telling you what you want to hear. Do not just go to A+E. I know the service has a bad reputation, but call 111 and tell them exactly how bad the pain is, chances are, they will send an ambulance (not an emergency one, just a spare whenever they can). You get pain relief much faster this way too as they can give you entinox until you reach the hospital. At the very least I expect 111 will arrange an out of hours doc appointment at your local hospital. I realise this post is coming across wrong at this point so I shall switch to my actual experience rather than 'advice'
So, at least once a month this gets so bad, and goes on for too long for me to cope with it at home. When this happens I call 111 and 9 times out of 10 they agree I need to go in and they will send an ambulance as soon as one is available. I have been advised NOT to make my own way in as my pain gets so bad that I often pass out with it, or get kinda stuck in one position where I can't even walk. Ambulance ALWAYS give me entinox which really takes the edge off. At hospital they give me a few shots of morphine until the pain is under control then send me home. I often break down and tell them I am sorry for wasting their time but I am always told that if the pain is bad enough to have a grown adult in tears and unable to move, then A+E is the best place for me. A+E are much more likely to arrange for scans and such to find out what the actual problem is too..they will usually do that WHILE you are there. While I am still undiagnosed..its not through lack of trying. I have to say the NHS has been amazing to me.
Pain clinic...I know you really don't want to hear this but don't get your hopes up too much for that appointment. I did and I was crushed. The one here may just be bad but honestly, its no different to a GP appointment except for the fact that they don't actually perscibe anything to you, they will send a letter to your GP and its still down to your own doc to actually write up the prescriptions.
In short, I would say A+E are great if the pain is so bad you feel you can no longer cope. But likely all they will do is get it under control then send you home, but when its horrendous thats all you want, even a few hours is a relief.
I hope you have a batter experience than me with getting it sorted but I have had pain 18-20 hours per day averagely. It is absolutely horrendous for maybe 3-4 hours per day (usually on a night, luckily as I have young kids) but even when its not at its worst its really painful. I had an operation to remove my gallbladder as it was suspected that may be the issue, it wasn't...AND the operation had a bunch of complications which have left me in more pain than ever before as I think I have nerve damage to go with whatever the hell I had before, as I get the feeling that the 'drains' are still stuck in my chest from where they had to drain everything after the staples and such came undone. Not good. My pain clinic are now on about me seeing a psychotherapist to work on ways to mentally deal with long term pain, as they say its pretty much the end of the road now and everything that could be done has been done. I do have a physio appointment next month that I am hesitantly optimistic about though. It has been spoke about me maybe seeing an anesthetist about having some form of injection which will apparently work similar to an epidural on the area that the pain is centered...but this is after 2 years worth of pain clinic appointments, MRI scans, operations and such, a ridiculous amount of painkiller changes, and its a very very last option as nothing else seems to work.
I know some people will not like this post as its not...supportive as such. I just think being realistic is better. Do not get your hopes up too much about the pain clinic as its not very different to seeing your GP, except the appointments seem shorter and less personal.
I really really hope you get this sorted hun as there is nothing worse than living in constant pain. I feel like a write off and I am only 29 years old. I was absolutely fine too until my son was born, after that this pain just took over my life completely.
Do they know whats actually the cause of your pain? Have you had scans and such or were you just chucked onto painkillers immediately? I would also suggest maybe changing GPs if yours is totally useless. I know thats not an option in some areas though...