Well did you clean it?! 
I wouldn’t necessarily say your visuals have a spiritual meaning. Just like Laurie recently said in her post: Is This A Sign? Not everything has to be a sign!
What you can do is go again into a deep meditation and repeat the exercise. Make sure to have a pen and paper handy and draw the symbols again. It could also be a sign of your personal symbol.
If you do that, make sure to take a picture and post it here! That way we’ll be able to help you identify whatever it is!