Worst travel experience when coming back from holiday?

Getting altitude sickness in the Andes. I was so sick. By the time I got to Cusco, which is still 3400 metres, I had chronic apnea and exhaustion, falling asleep and waking within a minute gasping for air - for 12 hours. The doctor basically told me get the first plane you can out of here or I need to hospitalise you overnight with oxygen. You could die. Oh, ok. Booked the next flight and checked out within ten minutes, had no accommodation booked in Lima, just left without my son and his partner. Had to message my son who was out touring that I was heading to airport. He booked something for me in Lima. Within 30 minutes of being in the air in pressurised cabin I felt normal. And his partner was constantly rude to me for the entire trip and the way home, so I moved my seat forward in the plane home so I wouldn't sit with them. Then the airline had cancelled my connecting flight so arrived half a day later than planned. It was a horrible trip.

The funeral of my mother. 😞

I remember specifically because it was the day Muhammad Ali passed away. I was returning from a conference in CA. Flight landed about 11:30 p.m. and once we deplaned I went to the restroom. Got to baggage claim, all luggage was gone and had been locked in Delta's office and they were gone for the night. I ended up spending the night in the airport because I'd left my car keys in my luggage. The Delta counter opened about 5:30 a.m. Needless to say, I did not sleep. Once I got my luggage, it was another hour before I found the correct shuttle to get to my car.

Probably a delay by mechanical breakdown on the cross-Channel ferry.

We not only left Cherbourg some four or so hours late, but that meant we missed the tide for the Channel Islands harbour so had to creep slowly across to there while the water came up again. Another four-hour delay.

The voyage effectively lasted all night, arriving in Weymouth at about 8am instead of (I think) midnight. To their credit the crew made the hot drinks free.

I didn't have far to drive further and the delay did not really affect me too much personally apart from making me very tired; but one passenger told me she was faced with driving all the way to Glasgow, about 400 miles North.

The jetlag flying from Sydney to LAX was horrible, but probably the worse was spending most of a day at the Houston Airport praying that our flight would not be cancelled. We got to the airport very early not so much for fear of flight cancellation but because of the warnings of potential flash flooding making the airport inaccessible. Heard a businessman coming off a plane say, "ah, as soon as they open that airplane door and I feel and smell that humidity, I know I'm home!"

You mean coming back from vacation

Greyhound there and back
Terrible

Infected tooth. Went to hospital twice for pain meds. Had to turn around, drive through the mountains to go home. Car breaks down in the mountains. Tow the car to nearest town. Emergency dental surgery. All of this cost a fortune.

Having a hour to change planes from Halifax to Toronto. To Toronto to LAX thanks to Air Canada. When coming back from Canada. Had to rush like crazy from one end of the airport to the other end.

Getting Covid from a guy in our row coming back from Costa Rica. Coughed and snorted hours next to us. 😏

Coming home through JFK. Had a terrible experience two times. Avoid that airport if you can!

Heavy snow on the runway.

Coming back from Dubai. Memorial day The trip itself was fine but apparently some of the people got sick from traveling throughout Mecca. So when we landed the news media made it seem like we're infected. I had to go to a special part of JFK just for quarantine airplanes. It was crazy and the sickness turned out to be a flu