I survived my second session running my game, and I even had a lot of fun doing it. Still had some wack-a-doodle attendance issues, two players are still MIA, one who was there last game couldn’t make it for school reasons, but on the bright side my Cleric decided she was up to playing AND I had a new player join us.
I got the message about the new player only a few hours before game so we started late to give him some time to create his character. I corralled all of my PCs to a tavern where my barbarian was asking if anyone had seen his tribe by way of saying “Have you seen anyone like this?” and pointing to the crest on his shield.
The running joke was everyone asking him how you lose a tribe.
My players caught onto the hook I had planned with the missing family. They spoke to a silver smith who was upset his apprentice had gone missing and negotiated a reward for finding him. They met a thief (New player) who could show them out into the slums where the missing family lived.
With a massive bluff roll our thief stole the house from squatters claiming he’d bought it and the paladin who’d waited behind was his personal guard. He then put a large for sale sign on it and asked an exorbitant price.
The Barbarian found an iron skillet that had been thrown into the river from the boat the family had left on. It piqued curiosity since the apprentice was a changeling. They found out that the family had traveled north on the river.
They used knowledge local to figure out what was up north. I said it was toward the city proper, and then they asked what was beyond the city and found there was nothing until you reached the border with the next country. They did not check the city. They decided that the family must have fled the country.
Well crap.
I’d hoped to get them to check the city itself outside of the slums, but they ran off into the wilderness. Now they are at the border and headed toward Queen’s Portal. Interestingly this brings them back by an abandoned hook from the first game. I ended game when they got to the border because I am not yet very good at planning on my feet.
How am I going to get them back to the right country? I don’t know. I don’t want to railroad them but almost all of my planning for the campaign centered on them being in this country at least.
We’ll see how it goes from here.
I’d love to know what a more experienced DM would do in my shoes. I’m a little out of sorts but I still have a week and a half before my next session. Surely something can be planned in that time.
RPG Lady 
One thing you can do is simply make all the plot hooks, NPCs, Maps etc, you have already planned are no longer in the city that you hoped they went to but rather are in a new city just over the border in this new country.
If the PCs were supposed to search City A for the lost apprentice, it turns out that they made a lucky guess because the apprentice actually went to City B, the new city. You can use all the maps and any other resources you had planned for City A, but just cal it City B now instead!
If they ever head back to the old City A then you would hopefully have advanced warning and can mke a brand new City.
Remember the PCs dont know what city is what, only you do and you can always change that as the plot develops. Any time they go off the tracks they end up at the place you wanted them at it is just in a different location
This is a useful tactic you can use for the whole of your DMing career. they are supposed to search a ruin to the south but head north? Thats ok the ruin is now north, the only thing you cannot do is move something AFTER you have told them where it is.