The pains you are describing @SuperProudMummyOfTwo
do not sound anything like the imaginary sort of pains that someone may get if severely stressed. However, I am not a doctor, but I believe that your pains are absolutely real, and what stress can do - particularly health related stress - is make us focus more on any real pains, which can then make us involuntarily and non- intentially, and probably unknowingly as well, tense our muscles which may then cause the pain we are feeling to increase to a lesser or greater degree.
Dear OP, I really feel for you, and as someone who also had the medics believing my symptoms were "all in my mind" - and if they really believed that, then why didn't they arrange for me to have intensive mental health therapy - as that was many, many, years ago, when we still had a reasonably well functioning NHS.- until they eventually did enough tests that they probably stumbled on my diagnosis, rather than expecting to find it from the beginning - and no, my disease/condition is not some rare, hardly ever come across, illness!
Anyway, back to you OP, if your left sided pains did not start until after, at least your first Caesarean, then the first thing I would want to rule out as your GP - by your GP conferring with a Gynaecologist, not him just asking for you to go on to the back of their very long waiting lists - is whether your pains could have been caused by internal scar tissue forming after your sections. If that is the cause of your pain, it could - but not a definite would - continue to get worse, if for example, any scar tissues already there, were pulling on, and possibly slightly tearing, some more tissue, that could then lead to even more scarring on the new internal wound.
Now the likelihood of me, as some random Mumsnetter (slightly intelligently) guessing, the correct diagnosis for your symptoms, must be quite - if not, very - low, so I am just suggesting this because (through some personal experience) it seems like the most likely candidate to me. Another cause of the pain - again to do with your Caesarean sections - could be a slightly more worryingly accidental tiny tear made in the wall of your bowel during one of your operations, but I see that as a less likely cause, but still one that both your GP and Gynaecologist should consider, before tacking you on to the end of any waiting lists.
So, before the Gynaecologist even sees you, and to save both time, and hopefully, your severe discomfort lasting any longer than is absolutely unavoidable, you should have 'another' wide spectrum blood test, followed by whatever "they" would consider to be the most useful scans. If it were my choice, I would arrange for you to have an ultrasound, followed hopefully on the same day - for your convenience, and for them to get, what may be very useful information, much more quickly and efficiently than waiting for each individual result - by an MRI scan of the same area. I know that MRI scans are expensive, but I believe it to be a necessary tool in trying to discover the cause of the distressing pains.
Whatever is causing your pain, Super Proud Mummy, I very much hope that it gets sorted very soon, as expecting you to wait 6 months just to start trying to find out what is causing your pain, is both cruel, and in my opinion, disgusting. As for your excessive tiredness, well any physical pain and/or mental pain, and anything in our bodies that are not working to optimum levels, can cause us to feel exhausted, but there is something else that is almost 100% guaranteed to cause us massive, debilitating exhaustion, and from what you have told us, you have two of them 😜
In all seriousness, it is probably a mixture of being a mummy to two tiny tots, while also suffering almost relentless pain, that is causing your excessive tiredness. Although, I am presuming that you have had your iron levels tested quite recently, but if not, then it is an easy test to do, of course, iron levels are also tested in the wide spectrum blood test that I think you should have done, again unless you have had one done very recently. 🌸🌸🌸