Congratulations! You are just like Harry Potter himself. When Harry was about to get sorted he had the following thoughts:
Harry smiled weakly. Yes, trying on the hat was a lot better than having to do a spell, but he did wish they could have tried it on without everyone watching. The hat seemed to be asking rather a lot; Harry didn't feel brave or quick-witted or any of it at the moment. If only the hat had mentioned a house for people who felt a bit queasy, that would have been the one for him.
A horrible thought struck Harry, as horrible thoughts always do when you're very nervous. What if he wasn't chosen at all? What if he just sat there with the hat over his eyes for ages, until Professor McGonagall jerked it off his head and said there had obviously been a mistake and he'd better get back on the train?
So here we have it. The great Harry Potter, The Boy Who Lived, The Chosen One, also thought that he didn't have any of the qualities that the houses were looking for. He seemed to think that the hat would be unable to place him anywhere, and he would be sent home.
But in the end the hat managed to dig deep inside his mind and find some Slytheriny qualities. So it's likely the hat could do the same for you. As far as we know there is no student that the hat was ever unable to place in a house. Moreover, even if there were absolutely no qualities that you had, and the Sorting Hat had no way to decide where to place you, it is still possible for you to get sorted. Recall what Harry told his son Albus in the Epilogue of Deathly Hallows:
But if it matters to you, you'll be able to choose Gryffindor over Slytherin. The Sorting Hat takes your choice into account."
"Really?"
"It did for me," said Harry.
So if you're sitting there under the Sorting Hat and it's drawing a blank, if you hear that little voice saying "I have nowhere to put you because you have no qualities", then your best bet is probably just to beg the hat to put you in a particular house, and pray that Harry was correct that it really does take your choice into account.