Wait till the second result and do the third finger prints.

Ususally (from what I read), FBI does security check through computer. If computer result is clear, you sure pass background check fast. Once there is problem (as unclassified, I guess), they will do manually, taking time.

If you don't have bad record before, don't worry. After this third check and wait for about 2-3 months, send inquiry to USCIS. Your district senator or congressman is also a help source, ask them to do inquiry too.

You will be fine. Take it easy. When did you file your 485? Waiting for one year is very normal.