just learnt a lesson

I have been using the igmarkets platform in demo mode for a few weeks, thought I had it worked out so I opened an account, deposted some money, not much $4500, and started trading.

I placed an order this morning, buy BHP at 36.65, this was above the close of trade on Friday of 36.61.
I set a stop loss of 15 and a sell limit of 40.

buy 36.65
stop 36.50 my stop loss of 15
sell 37.05 my limit of 40

The markets open, BHP opens at 37.65, a full $1 above mt buy price and 60cents above my limit. I think wow thats great I just picked up around $300. I check my account balance and nearly fall off my chair, it says I made a loss of $150, so with commission, around a $230 loss.

I ring igmarkets and am told that BHP opened higher than my buy of 36.65, the guy says, so we get you in as fast as we can at the best price. He says the best price they could get me was 37.67, They keep my same set loss and limit targets, so now stop loss at 37.52 and sell limit now at 38.07. The support person said I needed to use buffer limits so that it doesn't happen again, I was not aware of them, so I guess the blame for this loss is mine.

I had been trading this way for the last 3 weeks in demo mode, my trades all went through at the levels I set, buy, stop, sell and limits.

So what do you think, my bad luck that the best price they could get me was 37.67, and guess where my stop got filled at, the low, of 37.52, I wonder if the entry price would of been the same if I had a stop loss of 20, I have a bad feeling their computer platform is set to trade in their favour.

Now I am off to learn about their buffer limits to see if it would of made a difference.