The only value a stock has is what it is the day it is sold. If your the market says your stock is worth $100 and you don't sell it, then it doesn't give you anything. So just because the DOW was 'valued' at 25K, it didn't mean squat unless you sold it.
Stocks are for the long term. Always buy for the long term, and never ever ever ever panic when the market turns. Because you sure as heck weren't breaking out the champagne when it was seriously overvalued.