Would recommend endocrine evaluation, but it may not be thyroid/endocrine related.
The low potassium could be an adrenal problem, but other causes will be considered by the doctors as well.
I'm new to this site (Still waiting for a response to my question as well), but I can tell you this....Go see an Endo. Go with your gut feeling, do not wait. Our bodies give us warning signs and we need to listen to them. I wish you the best of luck.
Take Care,
bmxdad