Well done on getting to the transition stage!

After you think you woken up in a WILD, always do a reality check. Here's what's said on the Five Phases of WILD tutorial:

Blackness. Sometimes you will exit transition into blackness. This can be very frustrating because most likely you will assume that you are back in the relaxation phase and have failed. If you find yourself in this situation, open your eyes slowly. Chances are that you only have your dream eyes closed and will be opening them into a lucid dream.
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You could well be in a dream if you feel like you are laying there for hours, so always do a reality check when you think you have woken.

Good luck!