Omggg Lily, this was adorable.
I love the idea of Oliver having feelings for Cedric. I find it super, super believable - I can't imagine anyone putting up with Oliver's Quidditch fanaticism if they weren't also a Quidditch fanatic. And I can also see how the discovery that he has feelings for Cedric would freak him out enough that he'd sleep through practice (!) - inconvenient crushes can definitely have that effect, even on Oliver Wood. :P
I loved Oliver's awkward attempt at a joke, too, and Cedric's reaction was perfect. He's definitely got it bad - Oliver wasn't exactly subtle, but Cedric was really looking for any excuse to kiss him, wasn't he? So, so cute. <3