Yes, your high TSH, your TPO ab test and enlargement of the thyroid gland all indicate Hashi's. Your PA concluded subclinical hypothyroidism only because your T4/T3 were still in range; however, the ranges are far too broad, due to the erroneous assumptions used to establish the ranges. So, results within the ranges do not preclude hypothyroidism. Unfortunately many doctors do not understand all this and resist treating a patient, even with symptoms of hypothyroidism, unless the test results exceed the range. This is wrong.
Symptoms should be the most important consideration, followed by levels of Free T4 and Free T3. So before further discussion, please tell us about your symptoms and also list the actual results of your T3/T4 tests, along with ranges shown on the lab report.
In the words of an excellent thyroid doctor, "The free T3 is not as helpful in untreated persons as the free T4 because in the light of a rather low FT4 the body will convert more T4 to T3 to maintain thyroid effect as well as is possible. So the person with a rather low FT4 and high-in-range FT3 may still be hypothyroid. However, if the FT4 is below 1.3 and the FT3 is also rather low, say below 3.4 (range 2 to 4.4 at LabCorp) then its likely that hypothyroidism is the cause of a person's symptoms."
In view of your numerous symptoms that are frequently related to being hypothyroid, and your Free T4 at only 20% of its range, along with your Free T3 at only 45% of its range, it seems clear that you are hypothyroid and in need of medication.
A good thyroid doctor will treat a hypothyroid patient clinically by testing and adjusting Free T4 and Free T3 levels as needed to relieve hypo symptoms. Symptom relief should be all important, not just test results. If the PA needs persuasion to get her to understand that treatment is needed, then I highly recommend that you read at least the first two pages of the following link, and then give a copy to the PA and ask her to reconsider treatment.
Then you can point out that on page 3 that the AACE/ATA Guidelines for Hypothyroidism state that:
“A guideline is not intended to take the place of physician judgment in diagnosing and treatment of particular patients”.
They also state that:
“We encourage medical professionals to use this information in conjunction with their
best clinical judgment.”
If the PA refuses to consider clinical treatment then you will need to find a good thyroid doctor that will do so. Also, since hypo patients are so frequently deficient in Vitamin D, B12 and ferritin, you need to get those tested and then supplement as needed to optimize. D should be at least 50, B12 in the upper end of its range, and ferritin should be at least 100.