Stock

I recently joined kaChing virtual stock exchange, a Facebook application, to trade. It's not that professional to trade on facebook, but the appplication is quite user-friendly and datas are quite easy to follow. The markets it trades are US, but it doesn't specify which, which caused me confusions for the last few days. I have invited a few of you to this application, please invite further.
Following the news last week, I decided to go long on Amazon, BP, McDonalds, Tesco and go short on Toyota and UBS. I made not-so-small profits on the first day, however still suffered losses which makes my portfolio underperforming compared to my target achievement, and here are the analysis.
The longs:
Amazon and Mc Donalds both posted high profits in the last quarter, especially Amazon which posted higher than expected profit. The news came in Thursday, and I quoted the long positions right after then, in order to benefit the daily gap of an enormous volume trades of both stocks. However, I wasn't able to trade right when the market open, hence couldn't benefit from this. I was still able to earn 8% of capital gains from the 17% Amazon intraday stock rise. McDonald however ended up 0.2% down, after a day trading in a fairly wide band. The problem of timing was similar here, as the automatic system, like in the Amazon's case, put my sell on when the stock was near its peak of the day, which was very early in the day. I therefore suffered a huge loss on this stock, but I'm hoping to recover the stock soon, selling it after achieving its targetgain. Tesco contributed a 2.2% rise in capital on its own trade, helped me gain over 10000, a reasonable amount for such a small trade, given its quantity was limited when I was buying. BP ended the day with a loss, as oil price went down. I went long for BP following the news Opec would cut supply, which was reannounced a couple of days ago, but I think that the real cut will come later, by then the stock would most definitely rise.
The shorts:
The reports show Toyota was likely to post the first loss quarter ever, which would have a significant impact on stock price. Being able to capture this, I shorted Toyota stock on Thursday and enjoyed its downward slope on Friday, earning over 80,000 on this trade. The short on UBS appeared to be a loss during the whole day, as stock seemed to go up all the time. I anticipated that the financial industry is not ready for a rise, when banks still post losses and, business downscales still exist. The set up of so called bad bank that absorbs toxic assets and insure profitable assets, and the news on bank bonuses being cut down might be the reason for this bullish behaviour, since it promises extra cashflow and a more promising performance.
If the trade was more realistic, I would have used option to hedge again this UBS position, since I quoted it short at risk and I knew it. Fortunately, the rise was not significant, thus I didn't suffer too much loss. But I expect a slight upward gap monday, and maybe I will have to stay in this loss for a little bit longer.
There is a site for UK stock trade www.bullbearings.co.uk . I registered on Friday, and haven't got time to trade on it.