If it is T4 type med like Synthroid, etc. then you might notice a slight effect, but not a big deal. T4 meds react much more slowly than those containing T3. If your med contains T3, then you might have noticed being a bit more tired than usual until your next dose kicks in.
For either case, I would not double up on your dose. Doubling the dosage could cause a short term hyper reaction.
What medication are you on?