Cultural differences can be somewhat of a shock for people who are not easily acclimated to change of country or region. It becomes even more difficult when you are not just a tourist but have to actually live in a place you know little about.

It's always a good idea to prepare for this by learning as much as possible before hand but in my experience sometimes there is no getting around the fact that as a foreigner you are bound to make a mistake or a two. I have done it a few times but thankfully I had people around me for damage control.

Not to be rude or anything but as long as you stick to major points, I do think that sometimes people need chill out :-)