The incredible player flinging cube(s)

I currently have a game, designed entirely in Unity, featuring a terrain, shaped with the ingame editor, a player object, a capsule shape character with the basic scripts for movement and looking, a light and a camera. I also have a few prefabs, a cube scaled to be 4 units tall, another scaled to be 4 deep 4 wide, and a last one normal, 1x1x1. Each prefab has a box collider and a rigidbody scaled to match. Now I have the scene set up so that it starts me off in a kind of a canyon with a couple blocks pre-spawned. I have a script set up such that when I click in a direction, a block is spawned about 2 units out in my line of sight. All of that is good and well.

BUT. If I have a few blocks down and I hit one of them the wrong way or jump on one of them the wrong way, I get FLUNG, like a rubber band off into no mans land. I want to know what is causing this, whether there is some sort of option I can use to stop this from happening. That is, I dont want to get flung away any more, I can easily set it up so if I go so far from the map I respawn at the starting point, that is no problem. I just think that for what I am making, such massive physics silliness will be a problem eventually, if it isnt now.

I managed to find the root of the problem after a couple days of halfway looking for it. I was using some scripts that were essentially the FPSInputController and CharacterMotor scripts converted to C# that I got from here: http://forum.unity3d.com/threads/fpsinputcontroller-and-charactermotor-in-csharp.93527/

I must have thought I would need my scripts to be in all C# so I could edit them easier and access variables in one without some rigamaroll to get the scripts to interact. But yes, the cause of the incredibly strange physics was the scripts posted above. Just thought I would say that here in case someone else ended up with the same problem.