Sorry for the reasons that have brought you to the forum, but I'm sure that you'll get fantastic support and help from the members. I have!
This first appointment is likely to be pretty standard; the consultant will want to do further tests - biopsy and bone scan - in order to check if it is cancer, where it is, and if it's spread. Then they will discuss your options. If you can update your profile with this info it will help members to respond appropriately rather than guessing!
Waiting is really tough but I suggest you download the Toolkit from this site which gives an overview of the various treatments (there are lots) and the pros and cons of each. I found it really helpful and it did lessen the panic a bit to get my head around the options, and realise the extent of the continuing research and treatments available.
Re what to ask... once you are clear about whether it is cancer, and what stage it's at, here are some questions that might help (suggested to me by one of the members on this forum when I was at the start of this journey):
1. What are the treatment options?
2. In each case, what will be the potential benefits and how rapidly will it be effective?
3. How long is it likely to be effective? (best-case scenario so that we stayed positive!)
4. When will it start? How, where and how frequently is it administered?
5. What are the likely side effects and what could be done to lessen them?
Good luck. Let us know how you get on.