Loss aversion bias derives from the prospect theory. Humans have a funny way of evaluating their gains and losses, along with comparing their perceived meanings against each other. For example, when considering our options before making a choice, we are more willing to give preference to a lower possible loss over a higher possible reward. Fear is a much more powerful motivator than greed. In practice, a trader with a loss bias is more akin to cutting profits when they are still low, while allowing bigger drawdowns.
The Aussie dollar is very dependent on the price of gold, as Australia is the 2nd largest gold producer in the world. If gold prices fall, this means Australia is getting less money for that gold, and generally the Aussie dollar will weaken in these circumstances. If gold prices rise this is great for Australia and their dollar will normally strengthen with the rise in the price of gold.
Since the market is made by each of the participating banks providing offers and bids for a particular currency, the market pricing mechanism is based on supply and demand. Because there are such large trade flows within the system, it is difficult for rogue traders to influence the price of a currency. This system helps create transparency in the market for investors with access to interbank dealing.
The problem is that this is where traders are most likely to succumb to overconfidence bias. It's not uncommon for traders to complete a winning streak and then believe that they can't get anything wrong in the future. To believe this is of course unwise, and is only going to end in failure. Make sure you always analyse your trading sessions and look at your wins and losses in detail.