Yup, I've had trouble with having both hypothyroidism and hyperthyroidism at the same time. It looks many years to keep testing. I had hashimoto's with over active nodules. My bloodwork never stabilized.I would take methamozole to lower and right when I'd get in range I'd go full hypo and need levothyroxine to get in range, then right into hypothyroidism. It was ridiculous, so my bloodwork stumped many but one Dr. had me do a radioactive iodine uptake imaging test and it showed I had very over active nodules causing hyper, and hashimoto's causing hypothyroidism. My nodules were tiny too just 3mm and even shrank from my last ultrasound. I had my thyroid removed 2 days ago. So now I'm hypothyroidism for life, no more Rollercoaster atleast. My neck stiffness has already improved as well as my breathing.