Any way I could have damaged my speakers?

Thank you all for the reassurance. Listening to Hell Freezes over - Eagles right now and sounds really good. Have to say, this hobby may not be life or death if you make a mistake but the serenity it can deliver is priceless.

Thanks for all the responses. It's interesting to hear everyone's take and different experiences and nice to hear that I'm not the only one who's made this mistake before.

@almarg ... Holy sh**t... What a technical explanation of what happened. A lot times in life, things happen that can't be explained or you think they can't be explained but you certainly did in this instance.

This happened with my favorite speakers that I've ever had so I'm just happy they're fine.

@almarg  "If the amp is powered up when that is done, as it was in this case, that could easily result in a brief transient being applied to the speakers corresponding to the amp’s maximum power capability, at an arbitrary combination of frequencies. With most of that power very possibly being in the treble region, where the power handling capability of the speaker is probably lowest. "

Could be that my saving grace was that I have a decware amp that only delivers slightly over 2 watts per channel?