Duplicate Vertices with Mirror Modifier

Hello Blender Community!

[PROLOGUE/BIO: Read only if you care] My name is Tanner, and I have recently begun to teach myself Blender through the vast tutorials and guides that the site provides, as well as YouTube videos. My main focus will be attempting to create 3D models meant for games, inspired mainly by Final Fantasy. I would also be interested in sculpting advanced models once I get the hang of this…
With that said, I have come across multiple issues and I am usually able to Google the issue and find a solution, but finding a solution to my current problem has not been promising.

I am having an issue when attempting to create a low-poly human model. Starting at the ankles, I use a cylinder mesh, of 6 vertices.

With clipping and a mirror modifier on, I extrude up until I’ve reached the crotch area where I need to connect them.

When I connect the two legs at the under-crotch (hah) I extrude the top two vertices towards the center, until it seems that it has been connected with it’s mirror counterpart.

Once connected, I shift select the vertices all the way around to extrude on Z axis for the torso/crotch/butt area.

And when I try to extrude…

I was able to pull apart the multiple vertices that I found.

If I need to attach the file here, please let me know, and I will give it a go.

I would appreciate any assistance or alternate methods for creating models. I will continue to watch tutorials, and hopefully find a good way for me to blend it up![INDENT=3]

Thank you for your time, and best of wishes.[/INDENT]

Basically it should work like you did; on your first image, you have created already duplicate vertices. You can see that, if you select a vertex, the connected edge is always highlighted, like X++±–x (X selected vert, x, unselected vert, + highlighted part of edge, - unhighlighted part of edge). Now if you produce duplicates ontop of each other, it looks like Xx------x.
Extrude does two things at once, creating new vertices and putting you into grab-mode (letting you move the new verts). If you abort an extrude with RMB, you abort only the movement, but the new ones are still there.
Anyhow, your problem should be solved by using “remove doubles” from the toolbar.
Actually I dont know why you have triangles in there; maybe something else is going on too. See if the above helps you already, though.

Thank you, kindly. I will try this out now.

And, yeah, while working with my new model, (which is progressing well), I have been able to find exactly what you’re explaining and merge the duplicate vertices into one. But I feel like I shouldn’t have to do this, and I don’t understand why it’s creating 3 vertices when I extrude up once.
While extruding the head of my model, it also created duplicate edges and faces, which I had to go in and delete, and then re-face. I’ve tried Remove Doubles, and if I can guess, I assume it will take any verts within the merge distance amount and merge them. Should this activate while extruding?

Again, thank you very much for your reply. Feels good to know there is somewhere I can go if I have a specific issue.