<human>: Hey there Docs,

I have some questions about thyroid diseases. I'm a 23 yo male, 5'8", 140 lbs. When I was 11, I was diagnosed with Hashimoto's. I've been on levothryoxine ever since, and have been on the same dosage (100 mcg) now for about 6 years, pretty much since puberty. It was totally under control. About, oh, 4 or 5 months ago, I started experiencing very subtle symptoms uncommon to my normal life. Anxiety, low energy, nonexistent sex drive, lingering feelings of depression. I was in a brand new environment, and while I was very confused about why I was reacting this way, I chalked it up to life. Fast forward to about two weeks ago, and my resting heart rate was about 110. I was experiencing palpitations, lack of sleep, and my anxiety was through the roof. I went to my doctor, and found that both my TSH and T4 levels were high. I've since had my levothryoxine dosage reduced to 75 mcg, and am about a week on that dose now. I'm starting to improve, definitely, and have an appointment with an endocrinologist next week.

My question is, how in the world did I go from from hypo to hyper? If Hashimoto's is autoimmune and part of my thyroid was destroyed, why do I all the sudden have excess? Is it possible to now have Grave's disease, or nodules? This is more of a curiosity, but I'd like to have some info. Thanks for any help!

Can you succinctly summarize the text in 1-3 sentences?
<bot>: Have Hashimoto's, have been hypothyroid my whole life, now all the sudden am hyperthyroid. Why?