This seems like a really simple set of questions but I'm having a really hard time finding the answers. Any help or tips would be appreciated.

I'm flying Phuket to BKK arriving at 0025 via airasia (assume I will have to pickup and re-check luggage)

Questions:
1. Can I check baggage into a cathay pacific flight to Hong Kong departing at 8.25am? Or do I need to wait till ~5am when most people would start checking in?
2. If I can checkin my luggage which lounges are available to me?
3. If I can't checkin my luggage then which lounges are avaiable to me?

I have a Qantas Gold frequent flyer card.

According to oneworld.com the only lounge open 24 hrs is Louis Tavern First /Business Lounge but I'm not sure whether I will be able to access it.

Any tips would be appreciated. It really doesn't seem worth getting a hotel. By the time I get my luggage, get to a hotel and checkin it would be about 2am and I would need to checkout and head back to the airport at about 5am.