I don't know. If I answered a question but nobody read it, did I really answer a question? 😄
If you wore a dress in a room that was totally devoid of light, would you be wearing it? Of course---your action of wearing the dress is independent of there being anyone there to be able to witness your action. (Sort of like saying God doesn't exist because there's no proof of His existence.)
In a similar manner, if a tree falls in the forest, it still makes a noise, even if there is no one there for the sound it makes to activate that person's ear.
Is there if an even when?
Of course you wore it, the first part of your question tells so.
My brain hurts. I'm going to say no since you said 'if' and you said nobody was there.