I've never felt unwelcome in a country, although there have been specific areas and incidents that have made me feel unwelcome in particular areas.

I've had stones thrown at my car, been greeted by semi-automatic gunfire, been told that "my sort" are thieves, had drugs planted on me, had local police attempt to extort money from me (separate incidents), had such an argument with a taxi driver that I jumped out in the middle of an 8-lane road, been threatened at knifepoint, and been warned for accidentally pronouncing a word that implied I supported an ethnicity that wasn't entirely welcome in that area.

But in those same countries, I've seen all sorts of hospitality - impromptu invitations into people's homes, to watch weddings, to chat and drink tea/coffee/whatever, to be shown round tiny local churches and mosques, driven round both rural and urban areas just for the company, taken to favourite eating places, and generally helped out far beyond what one could reasonably expect of a stranger. Oh, and once had the local newspaper out to interview me. They hadn't seen tourists in a while...

So, on balance, no, I've never felt unwelcome in a country. Even if there were the odd few incidents. You get those at home, too, of course (and I'm feeling less and less part of the country where I live of late...)