Got filled, 20 cents above ask

So I woke this morning and was watching the markets and the nice little rally they were staging and I had hit my goal for my swing trade so I decided to sell my shares for the nice profit. However when getting into by brokerage account I saw that they had already been sold (2 people managing 1 account here). No big deal, then I checked the price and it was $.25 above what the stock was at that time. I've checked all the charts and the high of the day is still over 10 cents away from that price. I'm not complaining and I love that it happened although I feel for the mate that bought at that price. I'm just wondering if this is a common experience and if you can somehow take advantage of these weird fills?

Or was it just some unlucky shumck that instead of inputing 55.75, put 56.75?

Well, it's always worth a shot pre market to put in a high sell order. You will occassionally get lucky. The other day I sold a .50 stock for .69 premarket. It opeend at .50 and never went high than .51. Also, use limit orders.