middlecoin.com will not show you on the stats page for awhile - a few hours I believe.  You also won't get a graph (i.e. the number at the far right linked to your own graph page) until after a payout. 

As others have said, check your settings compared to the litecoin info page (even though it is at the litecoin site, the information applies to middlecoin.com mining and all scrypt coins).  If everything is working, your A: should increase, your R: should be 5% or less of A:, your HW: should be 0.  Your kh/sec should be within the ballpark of what others are listing at the litecoin hardware page.