Hello - Unlike thyroid hormone replacement, which actually builds up in the body over time, anti-thyroid drugs like Carbimazole are eliminated from the body fairly quickly. I'm a fellow patient, not a doc, but it seems that those two missed days could certainly have had an impact.
Another consideration is whether you had the labs drawn at different times of day, as TSH levels can fluctuate.
As for your symptoms, *you* know your body, so definitely take any major changes seriously, and contact your doc for a quicker set of labs if you feel your hypER symptoms coming back.
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