First, I am not a med professional so I am speaking just from personal experience.
Second, I have thyroid issues and, in fact, was diagnosed with both Hashimoto and Graves as I would move from one to the other because of the status of my thyroid.
Before I was diagnosed and treated, depending where I was on the continuum between over- normal and under-thyroid status, I would have anxiety, a constant adrenaline high, and/or depression . . . and, yes, it is good that the biopsy is benign . . . and, from my perspective, there can be issues with thyroid tests depending when the blood work is done . . .I went undiagnosed for over a year simply because of chance, I would get my blood work done when I was in a normal episode. It was not until a endocrinologist specialist gave me an open requisition and instructions to go when I started to feel odd that they saw the spikes . . .
Now, my question to you is: are you seeing a thyroid (endo) specialist? Now this is no negative to your doctor, but had it not been for my family doctor who said to me --- look, your tests fall within a normal range but that normal range is under scrutiny for its appropriateness and that he was more concerned with how I felt (everything from not being able to sleep because my overactive thyroid with all the adrenaline prevented it, to eating massive amounts of Hershey kisses and losing weight (about 30 pounds in a 5-6 week period) and then putting it back on (because I went into an underactive phase), he said that he wanted an endo specialist to look at things . . . so, my suggestion to consider: if it is a family doctor telling you that your hormone levels are "normal," then s/he may be operating on the standard range and you may want to consult with an endo specialist who will look beyond that and not assume that it is not thyroid . . .again, I am not saying that you do have thyroid issues, but there is more to a diagnosis than the blood work. Also, what type of blood work did you have done? TSH only? T3 and T4? How close are you to the outer limits of the range? Everyone is unique with respect to thyroid . . . a close friend has normal readings but was exhibiting overwhelming signs of fatigue . . . even falling asleep at her desk after 8 hours of solid sleep . . . she was put on a very very low level (in Synthroid there is something like 15 levels) of Synthroid and within 3 or 4 weeks it made all the difference in the world . . .and men are not immune either . . . a close friend's husband has an extremely overactive thyroid and until he was put on meds, he would sleep off and on but as he explained, it was as if the body was physically exhausted, but the head just was in full gear . . .
So, I am not saying your anxiousness comes from thyroid, just that sometimes you may have to dig a bit deeper . . . but, for me, I have had all of your symptoms and several others and I am simply grateful that my family doc did not rely just on bloodwork before referring me to a specialist who paid attention to how I was feeling as well as the blood work . . . .and, by the way, from what I am told, people with anxiety may often have thyroid issues . . . there is no harm in asking questions and getting a second opinion . . . . but, remember, please that what I have told you is my personal experience and I am not qualified to diagnose yours or anyone else's condition . . .take care, kc