Questions from Portugal

I went to Lisbon last weekend and had a great time. The city was beautiful, the weather was warm and sunny and the company at the hostel where I stayed was great. But the weekend has left me with some questions.

• When eating a whole sardine, do you also eat the head? I decided not to.
• Why do some people travel to distant countries to stay in a youth hostel and then spend the whole day asleep? There was this German guy who stayed in the same dorm room as me. He was asleep in the room when I arrived to drop off my bags at around midday. He was still asleep when I came back to change before dinner. He woke up briefly and appeared in the common room for about an hour during the evening and then went to the room to sleep some more. He left the next day. Strange.
• Why when I am on holiday in a strange city can I find my way around without a map but when I'm in my home town I always get lost?
• Why do all the photos I take when on holiday feature either (1) buildings shown from a steep upwards looking angle or (2) views that consist mainly of horizon? Examples of both from my Lisbon trip appear below, but I have numerous others from lots of different places around the world. I obviously spend most of my holiday-time looking straight up or gazing at some non-specific distant point on the horizon.

On another note, I learnt a new word on the weekend - it's Portugese and I'm not sure how it's spelt but it sounds like "saldage" or "saldadge" or something like that. It means the feeling of missing somebody, which may be happy (like when you're reminiscing about a really good time you had on holiday with a friend) or sad (like when you're missing a family member who's passed away). I can't think of any direct translation in English, so I'm officially adopting it into the language. Is there a process that needs to be followed? Do I need to write to the OED or something like that?