I've had so many unexpected events that I've learned to do a few things to make life easier while on the road:
Make sure you have a way to communicate. While my cell phone is supposed to work in most countries, I also have an alternate way of making calls. I do this with wifi calling. Some cell services, including mine, are set up to allow you to make phone calls while connected to wifi. Additionally, I use Google Voice to make calls since it is cheaper than my cell service. I also have a phone number with Google Voice that I can use in an absolute emergency.
Always check for local holidays when planning your trip. And not just the major ones. Twice, last month, I was surprised with local holidays where stores and restaurants were closed. Some sites as well. Luckily, I heard about them the day before so it wasn't as if I woke up to "surprise."
Confirm, confirm, confirm. I make all of my reservations direct with the supplier. Usually through an app. Always check the app to see your actual reservation, it's booked, and has the correct information. Take a screen shot of it. I don't know how many times I've gone to show the information--trains, hotels, flights--and I have issues with internet connection. It used to be where you had to call to confirm. Now all you have to do is either look at a confirmation email or at the app.
Google Translate is your friend. (Or any other language translation app that allows you to have a conversation, use the camera to translate printed words on the screen, etc.) Download any language files you may need ahead of your trip just in case of no internet.
This may be only for me....but....I have the belief that with just my passport, credit card and phone I could go from any street corner to home without going to get my luggage if necessary. I always have those three things on me.
Stuff happens. Don't panic. Know your options. If a train is canceled, is there a bus or flight I could take instead? (In an earlier example where a train from Dundee to Edinburgh was canceled, did the poster check to see if the FlyDundee coach, with direct service from Dundee to Edinburgh Airport, was operating? Or any bus service?)
Never cut things too close where it's out of your hands and you don't have some type of backup.