why is my new macbook pro running and loading really slow
OS X Mountain Lion: If your Mac runs slowly
The article is very cursory, but be sure to read through to the end. Unfortunately the link there is broken, so use this one: Disk Utility.
If it is new I suggest you contact AppleCare: 800-MY-APPL (in the US). Telephone support is free for the first 90 days.
Retrieving data ...