I'M SORRY!
Percy's jaw hung open as he stared back at Oliver, initially not knowing how to respond. The words that Cress had wrote him - It's awkward because you're thinking about it so hard. Just let it be a bit - flashed in his mind. Percy was being mental, but Oliver was a so adorably simple at heart and really Percy was probably making it worse by the way he was behaving.
Adjusting his eyeglasses, Percy stammered, "No, I... uh." He made a goofy sort a smile to help release his nervousness. "I had something on my mind." Which was true, but he didn't indicate what. "May we try it again?"
This time, when Percy hugged Oliver, he did so while trying to remind himself that he needed to calm the hell down before he did ruin their friendship.