My blackwidow tenkeyless keyboard is double typing every letter! HELP!

Hi. II got a rrazer blackwiddow tenkeyleess keeybooardd about a month andd a half ago, aanddd it has been doubblee typing letters forr the past month. this iss aan eenormouss issuee ffor me. as wweell aas doublee typing letteerss, my moveemeent in some FPS gaamees is haanddicapped beccausee of thiis problem. I orddeerreedd this keybboarrdd off of bbest buy wweebbsite I bbeelieve, do II have a wwarranty for this keyboard? this iss eextreemely ddisssapointing too me ffoor this to be happening to a NEW razer keyboarrd. PLEEASSE HEELP ME!