That just made my mind up, I won't be pouring no chills into the fermenter tonight, wait till the morning. Otherwise I might do the same. Or worse forget to put the yeast starter in.
After turning my "brewery" upside down - three times - I retraced my steps... OK I emptied the starter into the fermenter. Then 2 weeks later I remembered draining the fermenter and tipping the yeast trub into the garden.... Bingo! So I went rummaging around in the bushes and there it was!
Doctors sometimes leave stuff behind when they operate, that's one of the reasons they have all the tools and swabs laid out on a tray before an op... and then double check before sewing you up... and even then they screw up sometimes.