I am recent new to this game.  I've placed a goodly sum on a pet bid, and am outbidded by another person placing on money.  The bid ending time is not for many days, but since I am outbidded, why is my money not returned to me?   

Your money only comes back when the auction ends.

Say if you bid again, you are only deducted the original bid plus the difference, you aren't deducted both bids.