hey oooobs, welcome 
your name reminds me of Dr Who some how with the eeuuuds or however you write that.
you might want to share your story here too: [What huge dreamsign have you missed lately Part VI) <- most obvious missed dreamsign topic.
but since a discussion has evolved around this one I’m not going to merge it into that topic. 
having said that, your dream reminds me of one I had where I was in a classroom and noticed a big glass “valve” in the floor, with a sign next to it: “Lucid dream, enter here” or something similar 
I didn’t enter it
I wouldn’t say your dream was a dreamsign, but more a sign your subconscious is picking up on your desire to become lucid. I would classify this as a prelucid dream