I packed for a weeklong cruise with just a carry-on and a backpack. Here are 10 items I'm glad I brought and 7 things I wish I had with me.

The author packed for a weeklong cruise onboard Royal Caribbean's Wonder of the Seas, the largest cruise ship in the world.Joey Hadden/Insider

• I took my first cruise on Royal Caribbean's Wonder of the Seas, the largest cruise ship ever.
• For the seven-night Caribbean cruise, I brought only a carry-on suitcase and a backpack.

I recently took a seven-night cruise to the Caribbean with just a carry-on suitcase and a backpack. It was my first time traveling by cruise ship and while packing light made the trip easier, I did forget a few critical items.

The author's bags packed for her cruise.      Joey Hadden/Insider

Read more: I just went on my first cruise — here are 15 things that surprised me the most about this type of travel

One of the best things I packed was a magnet to help make my stateroom stand out amid a long hallway of identical blue doors ...

A magnet on the author's door.      Joey Hadden/Insider

Read more: Step aboard the world's largest cruise ship, which is so big it has 8 'neighborhoods' spread across 18 stories

... But I wished I downloaded some movies and shows to watch on my phone in my room since the cruise Wi-Fi wasn't strong enough for me to stream.

The author forgot to download movies.      Joey Hadden/Insider

During my cruise, I enjoyed a few beach days. For long days in the sun, I was glad I packed sunscreen ...

The author's sunscreen.      Joey Hadden/Insider

... However, I wished I had remembered to bring some aloe vera gel for the day I forgot to apply it and got burnt.

The author forgot aloe vera gel.      Joey Hadden/Insider

Some beaches in the Caribbean, like Tulum, Mexico, don't allow sunscreen in the ocean to protect wildlife, my excursion guide said. So, I was glad I brought a rash guard to protect my torso from the sun ...

An arrow points to the author's rash guard hanging up to dry.      Joey Hadden/Insider

Read more: I spent 7 nights in a 179-square-foot room on the world's largest cruise ship. Take a look inside my cabin.

... The ocean water was so clear that I wished I had brought a waterproof case for my phone to take pictures, too.

Clear waters at the beach in Tulum (L) and a waterproof phone case (R).      Joey Hadden/Insider, Getty Images

Read more: I went to the Caribbean for the first time on the world's largest cruise ship and wish I had more time in these 2 ports

This sunhat also came in handy to block the sun ...

The author wears a sunhat at a port.      Joey Hadden/Insider

... But I wished I brought an adjustable cap for windy days on the top decks when my sunhat wouldn't stay on my head.

The author forgot to bring a cap for windier days.      Joey Hadden/Insider

Even though the weather was hot during the day, this sweater came in handy for cool, windy nights and mornings ...

The author wears a sweater early in the morning.      Joey Hadden/Insider

... But I only packed one pair of pants and had to wear them every night. I should have packed a couple more.

The author wears the only pair of pants she brought.      Joey Hadden/Insider

I wished I'd brought a bar of detergent to wash my clothes since I packed light and laundry services on the ship cost extra ...

The author didn't bring detergent.      Getty Images

... At least I brought the right shoes: sneakers for walking around ports and waterproof sandals for the pools and beaches.

The author's walking shoes (L) and waterproof shoes (R).      Joey Hadden/Insider

Thankfully, I also remembered to bring a waist pack to carry a few things when I didn't feel like lugging my backpack around.

The author uses a smaller bag.      Joey Hadden/Insider

I was also glad I brought a digital watch to keep on ship time, the time zone that cruise ships stick to even while docked at ports that are in different time zones.

The author wears a digital watch.      Joey Hadden/Insider

I wanted to try my best to avoid illness and was glad I packed vitamins ...

The author brought vitamins.      Joey Hadden/Insider

... and also medicine to combat motion sickness, which I experienced frequently.

The author remembered to pack Dramamine.      Joey Hadden/Insider

More than anything, I wished I had earplugs to help me sleep during rough nights at sea, which sounded like thunder in my stateroom. It was especially loud since I was at the front of the ship, where seasoned cruisers said movement on ships feels the strongest. Next time, I'll come prepared.

Earplugs were the author's most missed item.      modustollens/Shuttershock

Read more: 10 things I wish I'd done differently on my first cruise, from choosing a better room to reserving shows in advance