Coolant Snafu help!

Hi All, Might have done something really stupid. I was doing a coolant drain and fill and filled just a little too much. No worries I thought and grabbed my hand pump. After pumping some out I realized the last thing I had used the pump for was gear oil. It had been wiped down beforehand but I can now see a slight oil sheen on the surface of the coolant in the reservoir. How big of a deal is it to have this trace amount of oil in there?

 

I wouldn't worry about either one, little too much, or the slight sheen, but wait a while and someone will tell you that a drain and double flush is the only way your going to avoid major damage.

 

If I were a smart man I would have drained it from the plug to begin with. However, I am not a smart man. I did do that after it had already been ran. Hoping not too much from the reservoir circulated during that 5 minute drive. Thanks for the replies guys, I appreciate it.