As Jay said it will need to dry, so in further answer to your question you will need to,
Take a putty knife and scrape off poly that didn't adhere.
Leave it alone for a few days, then using 150 grit screen or paper, light sand the edges around the spot and the wood itself, be sure to sand with the grain and go three to four inches aroung the spot. Next you apply some of the same poly feathering it onto the adhered poly, try to get the same level of coating as the first coat surrounding the spot, then let dry, after drying, screen (not buff) the entire floor, and add additional coat, then screen and coat for your final.
If you just put on a second coat there will be a noticable spot.