Hi there Omercivic,
Sorry to hear you seem to be encountering issues regarding your internet speed.
I have looked at your NBN FTTC SL service and run multiple tests and cannot see any obvious issues there. I would suspect the issue may possibly be internal and commonly to do with your equipment and with some help and guidence it may be something you are able to fix yourself from home.
Speed issues can be caused by various causes and internally a common reason is your WIF. I have attatched some helpful links below for you that are step by step guides in troubleshooting slow connections and WIFI connections, i recommend you have a look at them and see how you go.
For helpful tips on how to improve your internet speed,
follow our guide at www.tpg.com.au/slowspeed
To improve your WiFi connection, follow the steps in our TPG Community article at www.tpg.com.au/wifihelp
Also remember VPN connections, clouds and streaming sevices and incorrect WIFI settings will reduce your speed..
See how you go, good luck 
kind regards