Mistake still lingering in my head & partial fills

Aug 16 FXI limit buy 100 shares at 111.85 (Lowest low since May this year). Sold at 157.50 on September 18th. This trade is still lingering because FXI is currently trading at around 200 dollars, and the only reason that sell was made because I didn't cancel my upper limit order due to some stresses in my life. Simple error causes me roughly 4K-5K (that's a lot more than my post tax pay check).

To second guess myself a little more, I had been thinking of placing an option spread for FXI (something I don't do often), which would have played out perfectly. A few day ago I got that same idea thinking we are ready for another round of volatility, and then that sell off hits. Ahh... it really sucks to have a day job where you can't trade sometimes.

At any rate, I'm excited because I have two days to trade in November!!! Veterans day and the day after thanksgiving. Both are surely slow days in the market, but it still is good practice. I still continue to have success on these 'days off'.

I ran into a problem with how my trades executed when I traded during the last holiday. I took on a fairly largish position for me over the day in CHL (yes.. more China, but that's the kind of volatility I was looking for). At any rate, I went to sell 400 shares, and only got a partial fill of 145... ugh. The market was dropping and I needed to get out of the positions quick, so I canceled, reset my limit and was out. Saw some small profit slip away over a few minutes as I attempted to execute the order.

So not that big a problem in this scenario, but if this were automated I get in a really ugly spot. I go back and forth on this a lot in my head. When I trade, I typically use limit orders, however there is that danger of getting a partial fill. If I do a market order... I still may get partial orders, but more than likely the whole order will re-execute (at multiple prices). So in my automated system how do I want to handle this.

It's tough. The reason I got out of the position mentioned above was because a significantly dropping market in the last hour. Visually I could see (and I probably could compute the rate of change in the price to measure this phenomena). If do detect it, I have to cancel, wait for a cancel success, then execute the order at another price (if using limits). Awfully damn complicated. With market orders, I think it is a bit simpler (depends on how the broker handles it) however I think slippage could become a major issue in the scalping type algorithms that I am looking at.

So I think ideally what we want to do... when a price target is hit with limit, and there is a partial fill, just execute a market order to get out.