I have heard of people syphoning from the middle of the fermenterand leaving like 1/4 of the beer behind. if it is the early stages there is a chance it is just effecting the surface. Don't dump it without tasting it first though! I have had a couple questionable batches that looked off, but after a taste seemed fine. Kegged and carbed and it was all good.
Good luck and from now on Sanitize, Sanitize, Sanitize!