Q: Hardware Test and any assistance

I tried to do the Harware test by holding down the D key while starting up....only to find that nothing happens.  What would my next step be?  My computer is heating up quite quickly more on the left side of the keyboard in recent days and as I'm no tecno savvy, I would appreciate any help.

I don't have my Startup DVD's with me as we relocated to another country and they were left in SA. I've got a Mac Book Pro, Mid 2009, Mac OS X Lion 10.7.5

Could someone please advise what the next step would be, as I would like to locate the problem before I take it in for repair.