Henry gave Iestyn's hand a squeeze, delighted that he had given Iestyn this kind of joy. He didn't know if it was way too early in the relationship to say something like 'I just want to spend every day making you smile more than the last one'. Poor Iestyn had been through such pain, and Henry wanted to make his life a happy, joyful one, in whatever capacity Iestyn let him do that.
Instead of saying that, he said, "I just- Oooh, food!" when their food arrived.