Dr. Lupo does not participate on this forum.
You can find his forum on the right, where it says "related expert forums".
The answer to your question is yes. Blood tests can be in error. It is not common, but it can certainly happen.
That is one reason it is good to have a Free T4 run with your TSH test. You can compare the results and if one test is messed up, it will look odd when you compare the two tests.
You can also test hyper and feel hypo. Symptoms lag behind hormone level changes, and it's possible to be hyper a week or two before you feel it, especially if it is only mildly hyper as your 0.27.
Thanks your explanation about the lag makes sense. But the .27 does not.
8.63 on 50 mcg
.27 on 75 mcg
13.95 on alternating does of 50/75 every other day
the swings relative to the dosages seem improbable to me
I agree.
You had a partial thyroidectomy. The remaing thyroid was traumatized during surgery, and it may be sputtering, functioning irratically.
It's possible the TSH of 0.27 was an error. You may be in a phase where your thyroid is trying to return to normal function but is unable to.
I can't explain it. The only thing you can do is keep testing your levels until you become stable at the proper level.