No - you haven't made a mistake
Check out the Australian Investing Thread in the investing sub-forum - lots of advice there.
You should probably think about asset allocation - ie whether you just want to invest in the Australian market or diversify into international as well. Most here have international exposure and a 3 ETF portfolio (look for fund equivalents) of VEU, VTS and VAS is quite common giving you exposure to the World-ex US market, US market and Aus market.