Facebook – Why have the likes gone from 192 to 90 in a single mouse click

If you're targeting those countries, your ad is probably performing better there because the CPC or CPM rates for those countries is lower, so your ad is getting more impressions there than in other countries you're targeting with higher rates

If you're NOT targeting those countries, it may be a bug.

As for the specifics you asked about:

1. That's likely a cultural thing, you're also self-selecting because the spammy users with fake names are more likely to seek out the posts to comment on than users you're actually trying to reach - try to target the ads more specifically to reach the users you actually want

2. Is there some reason the middle-eastern fans are likely to genuinely like and share your page, or are you assuming that because they clicked the ad they're more likely to actually want to interact with the content?

3. this is likely due to the domain you're sharing links to having no solid reputation built up - link shares are pretty viral in many cases (see george takei's page or posts from The Onion for US-centric examples) but it takes a while of people interacting with your site's content before facebook's algorithms understand that the content is 'good' and should be surfaced instead of other posts

Facebook exposes analytics for pages with Page Insights. The Reach page (https://www.facebook.com/<pagename>/page_insights_reach) includes information about how many page views your page gets each day, and a list of external referrers.