Please someone help, double vertices and faces
 

Guys I'm having trouble with my vertices, I created a model in polygons and I seem to have double vertices and double faces all around the model. If I try to extrude something I have to select the face with the marque tool because there's a replicated face behind it. Usually when you model theres only one face and one vertice, but somehow I I managed to double my faces and vertices. I'm not quite sure why this is happening, can anyone please help me out?

you probably selected the model and hit extrude and didn't move anything at some point
i hear it's a common thing that happens.

in that case you can't really do anything other than either delete all the outer faces (and i assume you'll have to reverse the normals of the other faces) or start all over again (although since your verts already exist in the position you want them to you can always just grab a plane and and verts and edges and point snap them.

just be careful not to use the extrude and not do anything in future and you'll never run into that problem
that or else you might have duplicated the face and not seperated the meshes or altered the duplicated faces after duplicating
:)

Thanks for the help
 

Chirone thanks a whole lot, that was definitely the problem. Its no big deal to model over again, it was just bugging me that I couldn't find out the problem. Thanks again, a good luck with your modeling career. :)