Leaving Japan

Came to the Haneda International airport after catching up with friends of mine. One of the staff at the check-in told me I couldn't get a visa on arrival in the country I'm going to, even though there is no other way other than getting a visa on arrival. Albeit I showed him how to get a visa on the internet, the page of the Ministry of Foreign Affairs, he was uncertain about that and was reluctant to get me checked in. But after he called one of the governmental agencies, which often send staff to the country, he managed to understand how it works and let me in. Omg I might have failed checking in for the first time in my life! What a mysterious country I am heading to! I'm going to Singapore for a transit first!