Even a TSH of 3.753 is higher than the recommended maximum of 3.0; one doesn't stop medication, simply because TSH returns to the normal range.
When one is hypo for a while, the adrenals kick in to take up the slack for the thyroid, so it's very common for symptoms to worsen, as the body adjusts to having hormones it was doing without. Everything has to rebalance.
I suspect that your feeling awful is not due to the 25mcg of levothyroxine. You probably would be feeling awful anyway. You must have had a short bout of hypothyroidism - maybe from autoimmune thyroiditis - was the testing done for a reason? From the first test it would have appeared that you were someone who was a slow converter of T4 to T3. But at this point, perhaps just stopping the levothyroxine (which is T4) and watching and waiting, and rechecking in 4 weeks, would be the most product course. Also - consider whether anything else has changed. Any new hormones (especially estrogen-containing hormones) can mess up thyroid hormones), and the heart drug amiodarone can really mess it up.
While 26.08 is high, it's not really extreme, but I am surprised you have no symptoms of being hypo. There are people who do better with a higher TSH. In addition, TSH fluctuates as much as 75% over the course, of a day, plus it's influenced by many other things, so it shouldn't be used as the sole basis for a diagnosis or determining a dosage. The actual hormones, Free T3 and Free T4 are much more important.
What are the reference ranges for the T3 and T4? Reference ranges vary lab to lab and have to come from your own report. Are they Free T3 and Free T4 or are they totals? If not specified, they are Total T3 and Total T4, which aren't as useful as the frees.
It takes 4-6 weeks for the Synthroid to reach full potential in your blood
Actually, it *is* normal for symptoms to worsen or for new ones to appear, after one starts taking a hormone replacement med. It takes your body time to get used to having hormones it's been doing without.
It's typical for a doctor to start patients on a small dosage, such as 25 mcg/day, then increase as needed.