See if you can find an hour to go to a chiropractor before you leave. I know that your time is crunched, but when I started having pain, my back was the cause. It's happened twice-- the first time it eventually went mostly away after a week, and then came back ten times worse, twice!! I went to the chiropractor and it took a month to clear the pain.

The second time that it happened, I went into the chiropractor on the same day, and two days later I was pain-free. It's imperative that you do it right away, or else the nerves that are getting pinched will become inflamed and it will hurt you a lot more.

That might not be your problem, but the back can affect a lot of other areas, including your hips, and it may be the cause. Especially at our ages. Since it's not the hospital, and there are tons of chiropractors everywhere, you should be able to get into one without much or any waiting.