What's "Every day you make me proud, but today you get a card" mean? I don't quite get what this is trying to say.

What's this line mean?

This line means that this person who he now loves is more than someone to just tell his secrets to. If it were a short-term or less serious relationship, one might end up sharing secrets and being vulnerable, but he wants to do more than just that with her. Ex: I want someone not just to tell my secrets to. I want a deeper relationship than that. Ex: I found an outfit that I can wear not just for the wedding, but also for the party next month.

What does "head count" mean?

The word "headcount" generally can be used in two ways. Firstly it can be used to mean the way of counting the number of people present in a place. The second meaning is what is being used in this clip, it means the number of people employed by a business or company at any given time. Ex: The teacher always does a headcount to check how many students there are on the bus. Ex: The business is suffering so we are unable to increase the headcount.

What does "[something]'s up on the cloud" mean? Is it an idiom?

It is an idiom! The common phrase is someone's "head is in the clouds". If one's "head is in the clouds", it means they are disconnected from reality. They daydream a lot and live in their imagination. It's said as a criticism since they can be unaware of what is happening around them. Ex: Sorry, I had my head in the clouds. I'm listening now. Ex: Julia's head is always stuck in the clouds. Ex: You got your head in the clouds? Pay attention!

What does "satin" mean?

In this context, "satin" refers to a paint finish that is a little shiny. "Satin" usually means a type of fabric that is shiny and often used for formal dresses.

I assume there's a big difference between an original name and an English name for a nation. Then, where does the English term "Japan" come from?

Good question! The origin of the name Japan is not certain, but it's not English in origin! It probably came from the Malayan word "Japung" or the Chinese "Riben." In Japan itself, the Japanese call their country "Nippon." You're right in saying that the original and English names of countries can be very different! Some other examples: China, which is called "Zhongguo" in Chinese, and South Korea, which is called "Hanguk" in Korean.