Thank you so much for your question. It is my privilege to be able to help you.
There are many things that can cause an inflamed clitoris. the most common is due to trauma from stimulation, especially if it was injured and might have gotten infected. It can also happen if it is irritated by sexually transmitted infections, or sometimes it can be a varicosity (a swollen vein in the area of the clitoris.
Unfortunately, in order to have it properly treated, she needs to see a doctor for a proper diagnosis. It may be infected, in which case she will need antibiotics. She should keep the area clean, use anti-inflammatories for now, but she should see her doctor as soon as possible. I understand that you are going on a cruise tomorrow, so maybe you will need to find an urgent care center in your area. I know these things can happen at the most inconvenient moments, but unfortunately, I don't think that you have a choice.
I hope you find this helpful. If you have any more questions please feel free to ask me. If you are satisfied, please remember to ACCEPT the answer so that I get credit for my work. BONUSES and positive feedback are always appreciated. Good Luck! Dr. SaulJE