Did I Destroy This Coin's Value?

Welcome to CC!

1) NEVER use nail polish remover on a coin. It can and usually does contain more than just acetone (usually ethyl acetate) and those can damage metals.
2) Buy yourself some pure acetone, hardware stores usually carry it.

You didn't "ruin" the coin. If you can't even tell what it is, it must be cleaned, otherwise it's a useless chunk of metal. However, you could have done a better job at removing the foreign substance. Conservation techniques are best learned by experience, consider this your first lesson.

In general, you want to soak using what I have coined the "polarity ladder". For example, soak in order of decreasing solvent polarity (about 30 minutes each to start):

1) distilled water
2) acetone
3) xylene

I do a good bit of penny brick searching - this is simply a required method with many coins. It works surprisingly well. I use as hot of running water as I can stand and remove gunk with my fingers and sometimes a bit of liquid detergent soap. With these kinds of coins there are two choices - junk pile or a quick sink cleaning. Obviously, I prefer to see what I have before I toss it in the return to bank pile.