We thought of stress, but my life is actually quite great by most metrics - I don't have to work, great family, I was doing sports, eating decently well.
I would suggest investigating more the "eating well" part, you might eating something that you believe it's good for you but it's actually killing you.
I've been through a rough patch (approx one year) with many similar symptoms. At the end it turned out to just be basically stress-induced Hypochondria. I was manifesting all of these myself, and what got me healthy again was to focus on other things, and basically letting go of those anxieties. Easier said than done, but that was all there was to it. Anyways all the best, hope you get it sorted! :)