lost baggage

Hello.
I flew with Lufthansa the 6th September,....Porto to Frankfurt; frankfurt to sinpagore....almost lost the flight to singapore because the flight from Portugal was delayed....last flight was from singapore to Melbourne with jetstar.......
have no luggage thanks to jetstar...none of the companies tells me where my luggage is....im in Australia with no clothes,,,nothing...my holiday has become a nightmare....
called lots of times, no information, told me that i would get compensation and a phone call and nothing...this monday i fly to sydney and have no luggage...nothing!!!!

International
Singapore-Singapore
Australia-Melbourne - Tullamarine