Can't believe you used your mouth to attempt to blow dirt off the Sensor, bet you regretted that. For anyone else reading this comment; please do not do this !!
Also, please do not use any form of compressed air to blow inside your camera; this may also cause untold problems, similar to those described by the main reviewer. You will end up with more than air going onto your sensor and surrounding areas inside the camera body. Traces of aerosol propellants are often left behind on the sensor, contrary to what some marketing/sales brochures may claim - it is not worth the substantial risk.
Make sure the Camera Battery has plenty of charge (must be fully charged if attempting Sensor cleaning - this is a must do), set the camera (normally via one of the menu settings) to Manual Sensor Clean (you will probably hear a small noise - this is the Mirrow flipping up, this is normal), remove the lens (put a protective cap on the lens mount to prevent anything getting in) and turn the camera body so that the open lens mount is facing downwards towards the floor (not upwards to the ceiling or walls). Make sure you buy & use a proper blower; everyone I know really rates the Giottos Rocket Blower, I have one it costs around £8-9 I think. Put the blower nozzle close to the centre of the mount opening & squeeze the blower very strongly 4 or 5 times in quick succession. I would also use the blower on the lens mount (make sure you do this away from the camera body you have just cleaned) before you put it back on the camera.
This should get rid of all the dust allowing the particles to blow/fall down to the floor. Switch the camera Off (this removes the Mirrow lockup) and put your lens back onto the camera. Anything else left on the Sensor at this point will need more drastic action, like these cleaning pads or similar - hope this helps.