One bit of advice:
Always check your wallet/cash/credit card and passport before you leave... The rest... you can get there (generally anyways).
I did have an eventful trip one time...
I was on US PHL->DCA (->LAS) (cheap routing - tight connection, about 35 mins). Land at DCA and it took forever to taxi to the gate, the minutes are running down to nothing. Slow gate operator... I notice the captain is eagerly trying to get the heck out of the plane... turns out he was deadheading on the same DCA->LAS I was trying to get on. We both bolt to the LAS flight, it's closed. He knew the door code, lets me on, and the gate agent gives him hell for letting me on... By that time my F seat is gone of course (why they never give me one but always give mine away is puzzling), so I grabbed "any open seat", which turned out great as there was one with an open middle seat.

Made the flight just fine.
Another time, I was taking the same friday afternoon flight ORD->CLT every week at 4:30pm, but one week I booked an earlier flight to get in earlier, since I had a date that night. Forgot about the earlier flight, missed it, and missed the date too. LOL
HTSC