Sorry you are I am afraid correct
Most children are pain free the next day. Adults have pain for at least 3-4 days, and often have a second peak at c7-10 days.
Talk to your anaesthetist and ensure you hasve a decent analgesic regimen. There is no doubt that COLD is the best treatment - freezing cold drinks and icecream allowed to melt in the mouth work. You should also be shown jaw exercises as the masseter muscles are stretched by the gag and this helps the pain.
I would sugget you ask about staying in hospital overnight to get decent narcotics. I also routinely give narcotics to go home as part of an analgesic regime and there are some clever combinations
But remember one more bout of pain is far better than recurrent tonsillitis for years