possible contamination?

So, this is my 3rd all grain mash batch. I'd never taken a hydrometer reading before.
Basically, I was clumsy as **** and as I was attempting to siphon a sample of my wort to get a hydrometer reading, I accidentally dumped part of it out of the hydrometer flask into one of my 5 gallon fermenters.
The hydrometer flask wasn't sterilized, as I wasn't planning on it having any sort of contact w/ my wort/batch.
I of course from now on will just have a sterilized hydrometer flask which I'll dip in my wort.
Just wondering what people think about the possibility of contaminating my batch.
What would I be looking/smelling for when racking to the secondary or when bottling to tell if it's been contaminated/spoiled?

Thanks ahead of time for any input!

You can generally tell if it's been infected if it smells or tastes bad when racking or bottling. I always taste my hydrometer samples when checking the SG, and when bottling, and get suspicious if it's unpleasant. There are situations where this isn't the case, but it's worked for me so far. And that's assuming, of course, that you're not making something like a sour or wild fermented, where this might be what you're aiming for