Ricky -yep I'd say it's safe to assume you that you do have issues with thyroid. My CA/K is 8.25 and I have major thyroid issues - this can compound on your hypoglycemia issues also and vice versa. I have a sub-clinical overactive thyroid but low thyroid hormones output, hence hypothyroid symptoms and the low TSH strains adrenals, an 18 is probably sluggish thyroid (under-active). But only guessing here.
I find i can't eat breakfast at all as it puts me to sleep for most of the day. Hopefully I will see change in this once I get new NB supplementation regime. I've now stopped all Paramin and Zinc so would be good to see if i experience an improvement meanwhile.