I don't mean to sound callous, but you should have been taking some type of beginner beekeeping classes and inspecting your hive on a regular basis. As a new beekeeper you should be inspecting your hive at least every two weeks or more, if for nothing else just to see what their are doing and get the feeling for what a happy or unhappy hive looks and acts like.
That said, just because they made swarm cells doesn't mean they have swarmed. What is the population of your hive look like since you have returned? Do you have any new eggs or larva on your frames? Is most or all of your honey gone? A swarmed hive will have eaten almost all of its honey, and the population will be less than half what it was. Also the new queen (if you have one) wont start laying eggs for around two weeks after hatching out.
You should use some type of mite treatment in the next week or so to make sure your hive survives the winter. That hive will be over run with varroa mite. You should check to see if you have any bees crawling around on the ground near your hive with malformed wings or no wings. This is a sure sign of varroa infestation.
You would only make a split on a very strong hive, or to try to avert a swarm. The only reason a first year hive would swarm is if they ran out of room or had an issue with their hive, physical, chemical or parasitic. I other words water leaks(mold) that they could not fix, some type of poisoning, or mites, ant, robber wasps. You get the picture.
Finally, the only reason you would requeen at this point is if your hive didn't have a viable queen and they had no usable or young enough larva to make one on their own. You would have to do a hive inspection to discern that. Good luck.
Beekeeping is not a hands off operation no matter what you hear. The only way to succeed is to learn as much as possible and interact with your bees, only as it is needed, but it is needed.