I took a 13-hour flight to New Zealand from LA. Here are 8 mistakes I made.

Before heading to New Zealand, I had a 10-hour layover in Los Angeles. I took advantage of my business-class perks and spent most of the time between flights in the airport's Star Alliance Lounge. 

It was my first time in an airport lounge, so I naturally passed the time by sipping prosecco, slurping ramen, and relaxing on the outside patio. 

While I took advantage of the space, I didn't realize a representative for each airline was stationed in the lounge. That rep announced upcoming flights and let passengers know when each flight began its boarding process. 

I was on Air New Zealand's only flight out of Los Angeles for the day, and since I tend to be a nervous flyer, I walked over to my gate more than an hour before boarding started. 

It was a waste of time. I should've stayed in the lounge until the very last second when the Air New Zealand representative announced my flight was boarding. 

Before any flight, I try to squeeze a few laps around the terminal and a quick stretch break.

While I did a little stretching before my 13-hour flight, it wasn't enough. With such a long layover, I should've spent more time walking around the airport and exhausting myself for the upcoming flight. 

Looking back, I also wasn't active enough during the flight. The only times I left my business-class seat were for a few bathroom breaks, unlike some of my fellow passengers who were smart enough to take a few laps around the cabin.

This left me with avoidable achy legs and restlessness throughout the flight and into my first day in Auckland. 

I boarded the flight and realized my toothbrush was in the depths of my carry-on suitcase. Unzipping my overstuffed bag wasn't worth it, so I figured I'd forego brushing my teeth for the day. 

Since business-class travelers received a bag of toiletries from Air New Zealand, I was given a toothbrush, toothpaste, pen, lotion, and socks.

I was thankful I could clean my teeth, but the bristles were too soft, and the toothpaste wasn't as minty as what I typically use. 

Since I'm picky when it comes to oral hygiene, I'll remember to pack my own toothbrush and toothpaste for future flights. 

The luxury of an Air New Zealand business-class flight is that I was able to sleep horizontally instead of reclined upright in a seat. 

I assumed since I was sleeping in a normal position, staying asleep would be easy.

It wasn't, and I still struggled to keep my eyes closed in the unfamiliar space. 

When I struggle to fall asleep at home, I often take a bit of melatonin to help. While it's not for everyone, I'm not going to forget to pack melatonin for future flights. 

For most trips, I pack a few bars of chocolate since there will always be a time when I'm craving something sweet. 

I considered packing chocolate for my flight to Auckland, but I knew I wanted to try the country's beloved Whittaker chocolates and Cadbury Twirls. So I intentionally left chocolate off my packing list.

It was a mistake, and after dinner on the flight, I had a craving for my favorite sweet. I won't make that mistake again, and as I packed my bags to head home, a few of my favorite New Zealand chocolates were squeezed into my carry-on.

No matter how nice the plane cabin is, I find it nearly impossible to disembark from a long-haul flight feeling refreshed or energized. Unfortunately, the cinnamon-sugar pretzel I devoured at the beginning of the flight didn't help.

I should've remembered a tip I heard from a flight attendant: Don't forget to pack healthy snacks.

My future packing list will include healthier snack options since fiber and protein can help travelers feel better after a long-haul flight. 

Prior to boarding the Air New Zealand flight, I filled up my 34-ounce water bottle. 

Sure, the bottle was empty by the end of the plane ride, but it wasn't nearly enough to keep me from feeling sluggish and dehydrated.

According to The Aerospace Medical Association, travelers should consume 8 ounces of water for every hour they're in the air. While 104 ounces is a lot to drink in 13 hours, I won't make the mistake of drinking too little next time.

I made an error and took a nap when I landed at 6 a.m. local time in Auckland. 

I knew it was a mistake, but after the long flight, the hotel's king-sized bed was calling my name. As a result, I spent the next few days struggling to adjust to New Zealand's time zone.

With healthier snacks and pre-flight exercise, my fingers are crossed that future long-haul flights won't involve the same mistakes.