Arduino troubleshooting +only motor issues

I'm very new to Arduino and have been working on a project involving a 6V DC motor. I purchased a motor shield and everything was working fine, but I think I may have typed something incorrectly into the code as suddenly the motor stopped working. For a little bit, it would still turn for perhaps 3 seconds then stop.

Now, with or without the motor shield, none of my various sized/type motors will work, even in the most basic of layouts. However, I can still do basic projects involving LEDS. Does anyone have any ideas as to what might be damaged or problematic? I would really appreciate your help with this, as I'm kind of at my wits' end.

It sounds like your motor shield is broken. Did you draw too much current from it? Try replacing the motors with LEDs to see if it still works. There is little you can do with the software to damage things.

You provide no information about the motor or the power supply you used - without this we are just guessing. Which motor shield too...

Now, with or without the motor shield, none of my various sized/type motors will work, even in the most basic of layouts.

I do not understand this statement. How are you attempting to run the motors without a shield? What is a 'basic layout'. More details would help.