Fed_up, sorry or the delay in replying. Ask for a thyroid function test, ideally including FT3, as thyroidless patients don't always convert sufficient T3 from Levothyroxine and sometimes need the addition of Liothyronine (T3). Fast heart rate and sweating are commonly overmedication symptoms but can also be due to undermedication. Ask for iron or ferritin to be checked as iron anaemia can also cause racing heart. If your mouth is perpetually dry ask your GP to test for Sjogrens, which isn't uncommon in hypothyroid patients.
I'm not aware of association between hypothyroidism and Lipoma, which isn't to say there is none. Perhaps you could Google it.
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