Hyperthyroid | Atenolol

So. All my life (I'm 25 now) I've been incredibly 'in your face'. I've always wanted to be center of attention, I've played numerous sports, choir, etc.; stage fright was never even a topic. about a year ago I SLOWLY started to hide myself more. I became extremely insecure. I wouldn't make plans. I was a hermit. Up until about 4 months ago I could deal with it daily, until a had one of the most intense panic attacks I ever want to experience. All over nothing. I had so much coffee that day, I just chalked it up to that being the cause. Well, each day got worse, to the point of not being able to go to class, or work (I work customer service). I had to get checked out. My family has anxiety so I was assuming that was the diagnosis. My thyroid levels came back as TSH <0.005 and Free Thyroxine 2.02. Which is incredibly low and high. They diagnosed it hyperthyroid and I went in for a scan and uptake. Those results came back as my thyroid didn't absorb much of the iodine. So she prescribed me Atenolol to take daily. Which is a beta blocker, blood pressure pill. I HATED IT! I refused to take it anymore after a few days. I was beside myself. I felt like nobody understood me. I basically wanted to die. Then came another MAJOR panic attack. So I gave in, started the atenolol again. It's been 2.5 weeks. I feel better as in happier. I still mentally want to get anxious but my body doesn't tremble, sweat, and get dizzy. At least not the the point it was. My levels are now at TSH 1.100 and Free Thyroxine 0.70. Which is normal and low. But my weight on the other hand has increased. Now I know obviously as my thyroid stabalizes I will gain weight as I was losing it with being hyperthyroid. But this is like a bloated, hard stomach, pregnant feeling weight gain. Normal? Basically, has anyone experienced anything like this, or close to this, or been on this medicine, or can better explain my numbers. ANY insight is so appreciated. I will add my endocrinologist believes it to be thyroiditis, which I'm beyond unfamiliar with.