I was recently diagnosed with type 1 diabetes (spoke about it a bit in the mental health thread). Other than the age difference, my experience leading up to the diagnosis was the same. Knowing there is definitely something up with you physically but no clue what it could be, not until you finally force yourself to the doctors.
How many other PL players are type 1? There's bound to be a few, but I can't think of anyone else who is open about it. 100% it limits you, even if you're really, really fit otherwise. I doubt it's the main reason Dyche has barely used him, but it certainly won't be helping his cause. You can just physically crash and quite suddenly.