What is this song!!!!?? haha?

Okay i probally wont get to many answers but i heard this sing on the radio and i cant figure out the name the only lyrics i know are "Like diamonds on the floor" or it could be "dimonds fell on the floor" and then it says " and i cant help her" haha thats all i know and that might be wrong.. i think it sounds like Kris Allen but idk.. today was the 1st time i heard it. If u have ANY idea can u please help me? Thanks :)