Upvote:2
Yes, it seems OK. There's a slight change in timings in the first three sectors, hence the 'TK' code which indicates that a confirmed sector has changed times, instead of the 'HK' which is the default code for confirmed sector.
Nothing to worry about.
Upvote:2
As you've guessed, this is your flight itinary. It is in PNR notation, a format that airlines and travel agents use for data exchange. There is an online tool that decodes it.
There is already another answer on how to decode the fields - your case "TK2" means "timing change on this flight". Form the original times you have given, the first two segments only changed slightly, the third (number 5) will be almost 2 hours later than originally planned.
If that's okay is up to you. If you're not happy, you could reach out to Qantas if they'd re-book you onto another flight.