Ask the doctors about the results - but they usually exaggerate when things are "slightly" off. My opinion: don't rush into any solutions, and don't seek supplements.
What I can say is when I was 22 or so I didn't eat much red meat or eggs, and ate a lot of processed food, milk/cereal. I also ate nuts and pasta quite a bit.
At the time, I usually felt low energy, physically not as strong, and often tired. As for memory, anxiety, fatigue, this was also an issue.
Diet is probably playing some part in your problem.
I also had thyroid checked more recently but with good results.
I would try more fruit, milk, eggs, liver/red meat. These all have tons of nutrients which should restore energy. Menemen or shakshuka is a really good tomato/egg dish that I think instantly generates energy.