Why are there so many vertexes in the same spot!

Hi, i am trying to model my first model in blender. Its a bodybuilder man-shark XD. But anyways i extrude out and all that to make limbs and such. But i discovered that on many vertex joints and on many faces there were multiple vertexes and faces in the same spot! I am so frustrated. I have tried removing doubles. It doesnt work… if someone could help me and tell me how to stop this from happening in the future i would be really happy. It also wrinkles up almost when i apply subsurface modifier…

[video]https://drive.google.com/open?id=0B2HF0mIAcBpKaFdibWhneVU3ekU[/video]

increase the range of remove doubles