Auction settlement query

I had bought 3000 shares of a particualr scrip on a thursday @ of 40 and then sold the same the next day i.e friday @ 44 with closing price of 47.64.I receive the message on friday afteroon that there is short deleivery of the said shares.Then on monday the auction takes place. I would like to understand the following:-

1.In the auction bill it is mentioned as sold for you @57 and bought for you @ 50 and a total credit of about Rs.21000/.I understand that since i sold the shares before they actually hit my demat why is there a net credit for the same and not a penalty?

2.If i were not have sold the same on friday and sold on monday what would have changed? Would i have received the proceeds for twice the quantity since there are two transactions i.e the auction one and my own sell.

for eg- if i were to sell @ 52 myself on monday then would there be two credit transactions
i.e 3000 x 57 (auction) plus 3000 x 52( my own sell transaction)