Give more time to the technique. You usually uses 30 seconds, try 45 or 1 minute. The nose RC is your best bet.
Imagine your room before opening your eyes - visualize it - if you get in a hurry and try to open your eyes without proper visualization, you'll open your real body eyes instead your dream body ones.

I never FILD during the afternoon nap (that I take everyday), just during the night.