I take it you have already had your assessment, if so I will keep my fingers crossed for you that it goes well.
Unfortunately as Paton says, the rules of PIP have changed from DLA which used to be more about your conditions. Now PIP is more about how you cope on a daily basis. I agree though you would think with the lists of issues that some of us have it would be fairly obvious how we 'cope' on a daily basis - not very well.
If you haven't actually had your assessment yet then I would suggest you try and find a disability advocate who could accompany you to the appointment. They may be able to help guide you through it.
Sadly I think all these changes just seem to be designed to cut the numbers of people claiming and they don't really seem to be about how difficult we are finding life. It can happen though. I have in the last few months been awarded enhanced PIP for both elements and like you I have ME, Fibromyalgia and lower spine issues (plus RLS, FND, IBS and other things) so it's not impossible for them to see that you are struggling.
Bipolar, Fibromyalgia ME, Schizophrenia is now being linked to low FT3 blood levels, (Thyroid hormone levels,) carpal tunnel and some type of spinal degeneration problems can be down to B12 deficiency.
Damaged coccyx, osteoarthritis - an idea to check your vitamin D blood levels.
Sleep disorder can tie in with low thyroid as in adrenals/cortisol levels.
An idea would be to post your story up on 'Thyroid Uk' also here on Health unlocked.
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