I have worked with third world people all over the world. You would not expect an American or European to tolerate sticking a camera in their face without some sort of tacit permission first than why should we think third world people have less rights. No, what you need to do is smile hand up the camera to a neutral space in between you, smile and shrug. If the man smiles or reacts in a positive non-verbal way you have been granted his necessary permission in all likelihood. Still, move the camer towards your face and again shake your head yes than no- this is universal- and see that he is OK with this.
This is an ethical question. Even photojournalists do not stick camera near people. I suggest if you want a face full of frame without bothering people buy a 100-400 IS Lens which you can even use with a 1.4x II and keep at leat 18 feet back from your subjects. BTW, that is my handheld bird lens 560 mm that I regularly unless I need to pulll in subjects within a hundred foot reach and than I use 1120 mm on a tripod.
BTW, you are a native of some country too. Keep your respect for foreign cultures no matter where they are on the development continuum. Some of the finest people I have known were simple tradition society peiople with excellent habits of hospitality.
I`m not sure about the title, but this is excellent work. The title immediately leads the viewer to form an opinion of what they will be seeing even before the image downloads. I think that the look could mean many things...consternation, a serious intentness...etc. Of course, you were there.