Sorry, I just realized that the first link I gave you probably didn't work. Try this one instead.
http://hormonerestoration.com/files/ThyroidPMD.pdf
There are two blood tests used for Hashimoto's. One is the TPO ab you mentioned and the other is TG ab. Your doctor should run both, just to be sure.
If your doctor is evaluating your TSH level against the old range, he would say that it is in range. But the range was changed by the AACE over 8 years ago, down to >3 - 3.0. so your TSH is an indication of possibly being hypo, even though TSH is a pituitary hormone that is affected by so many variables that it is totally inadequate as a major diagnostic for thyroid. At best TSH is an indicator, to be considered along with more important indicators such as symptoms, and also the levels of the biologically active thyroid hormones, Free T3 and Free T4. Of these FT3 is the most important because it largely regulates metabolism and many other body functions. Scientific studies have also shown that FT3 correlated best with hypo symptoms such as yours, while FT4 and TSH correlated very poorly.
So I suggest that you should go back and request testing for Free T3, along with the Free T4 and TSH. If the doctor resists, then you should insist on it and don't take no for an answer. You may hear that if the doctor knows the level of FT4, then he can estimate the level of FT3 adequately. Sometimes this works, but if the patient is not converting T4 to T3 adequately, then the FT3 will be lower in the range than FT4. In view of its importance, why not just test and be sure.
Just because you are going to see an Endo does not mean that he will be a good thyroid doctor. Many Endos have the "Immaculate TSH Belief' by which they only rely on TSH to diagnose and treat a patient. Often if they go beyond TSH and test for Ft3 and FT4, they use "Reference Range Endocrinology" and tell you that any test result that falls within range, even at the low limit, is adequate. This leaves many hypo patients still suffering with symptoms. A good thyroid doctor will treat a hypo patient clinically by testing and adjusting FT3 and FT4 as necessary to relieve symptoms, without being constrained by resultant TSH levels. Symptom relief should be all important, not just test results.
If you want some insight into clinical treatment, this is a good link. The letter was written by a good thyroid doctor for patients that he consults with from a distance. The letter is sent to the PCP of the patient to help guide treatment.
http://sz0102.ev.mail.comcast.net/service/home/~/ThyroidPMD.pdf?auth=co&loc=en_US&id=178120&part=3
When you are able to arrange it you should also get tested for Vitamin A, D, B112, iron/ferritin, zinc, magnesium, and selenium. Hypo patients frequently are deficient in these areas as well. When you have test results please post them, along with reference ranges shown on the lab report and members will be glad to help interpret and advise further.