I get anxious over phone calls but definitely not that anxious. I'm just more hesitant but I have learned to suck it up and get it over with over the past couple of years.

I also used to have a lot more 'social hesitation' when I was in highschool and now I am still hesitant but much less so. Obviously, I am not a sufferer of Social Anxiety, which sounds like something you might be experiencing.

As for long conversations: I have issues with attention span a lot, sometimes to the point that I am trying to listen to someone and immediately tune out during the first sentence -- and this can be someone I love and want to talk to!