Hypothyroidism Support Group
Hypothyroidism is the disease state caused by insufficient production of thyrohormone by the thyroid gland. There are several distinct causes for chronic hypothyroidism, the most common being Hashimoto's thyroiditis and hypothyroidism following radioiodine therapy for hyperthyroidism. Advanced hypothyroidism may cause severe complications, the most serious one of which is...

It sounds like you're experiencing an auto immune thyroid attack which will cause brief "dumps" of extra thyroid hormone in your blood stream (causing the hyper symptoms) and then you'll sink back down to hypo symptoms again until the cycle repeats. It's just awful. When you have an auto immune thyroid condition TSH is almost useless - you have to look solely at Free T4 and Free T3.
I'm not sure about the medication question - I'm sure someone else on here will have an idea. But if you're unsure about this MD then I think you're right to get a second opinion!
Your complaints are common among people with an Auto-Immune Thyroid Disease (Hashimoto's Thyroiditis in particular):
Devlopment of nodules
A TSH that bounces like a ping-pong ball
Anxiety (EXTREMELY common in hashimotos)
Feeling tired then "hyped up" (sometimes in the same day!)
And MCTD (mixed connective tissue disease), Fibromyalgia, and other "all over" pain syndromes/diseases are commonly diagnosed in people with Hashimoto's for two reasons- 1) Sometimes they're really just a poorly treated thyroid and they resolve themselves once your thyroid is optimally treated and 2) Auto-immune diseases run in packs
And, you tested positive for thyroid antibodies:
TPO was 181(normal less than 35)
Which means you have a thyroid auto-immune disease where the body is actually attacking your thyroid.
Did the doctor(s) run any of the other tests like these:
https://labtestsonline.org/understanding/analytes/thyroid-antibodies/tab/test/
What about Free T4 or Free T3? Free T4 and Free T3 are typically what we look at to optimize a thyroid so that you have no symptoms or at least as few symptoms as possible.
The 300 mcg isn't uncommon, and the dosage itself isn't (whether that's high or not) what I would worry about, but whether or not you're getting the right dosage for YOU. The only way to know that is to get all those items above tested, then with your doctor (and us) decide what you need for YOU.
TSH is bit like looking at the oil gauge on a car to determine how much gas you have in your tank. It's useless....especially in auto-immune thyroid cases. USELESS.
Your doctor (most likely) is raising your dosage because you have nodules - medication is often used to shrink them so surgery can be avoided. And your anxiety may be under-treated hypothyroidism or a storm of antibodies attacking your thyroid.
I have this particular set of problems.
I'm going to throw some info at you, and when you're calmer, take a look, K? It's a load of info, but very valuable in helping you optimize your thyroid.
For now, remember: Get your Free T3 and Free T4 test - also ask your former doctor and the current one for copies of your labs tests and come on back with them.
http://www.dailystrength.org/groups/thyroid-resources/discussions/messages/17754063
http://www.dailystrength.org/groups/thyroid-resources/discussions/messages/17785295
PS Congratulations on taking the bull by the horns and learning more about your personal thyroid condition and treatment - it's the first step to feeling well again.
I'm not so sure I'm anxious as I am frustrated with my current Endo. Recently, he accused the lab of misplacing a decimal because my TSH went from 23.33 to 2.20 in a little over a week (one was drawn in the hospital and the other in his office as a follow-up). He said that TSH doesn't have swings like that. I'm definitely not a TSH expert, so I went with what he said. With the medication dosage, my pharmacy flagged this new dose as out of range (changed prior to US based on TSH) which is why I felt compelled to ask the question.
As for lab, the only antibody test they've done is TPO. They normally do a TSH and FT4 (listed in original post), but haven't done a FT3 since the day I was diagnosed nearly 10 years ago. I'm hopeful that the Endo I see in a couple of days will be able to sort things out and provide some clarification. I'm also hopeful that this new Endo provides more holistic care like my previous physicians. It really makes a difference!
Good luck with the new doc, it's always a gamble.
You really do need an increase in meds