I don't mind sharing...no need to include me/my name in anything, though.
I never considered myself agoraphobic but recently during some reading about the problems I *do* have I learned that some of my feelings are attributed to mild agoraphobia. Hopefully it will be somewhat helpful to you.
I started suffering severe panic attacks when I was about 16 (and I'll be 21 next month). I didn't know what it was, at first. I thought I was sick. Dying. They happened most frequently during this one particular physics class, and I remember sitting in my seat with my heart pounding so hard and fast it was painful, my body trembling so violently I physically was unable to write notes. I got cold and hot flushes, felt like throwing up, running away. I remember I used to dig my fingernails as hard as I could into the palms of my hands to try and ground myself or focus on something other than the totally irrational terror I was feeling. I ended up skipping a lot of school that year, either because I would start panicking in class and leave and go home because I felt so sick, or just not go to school because I was so scared it would happen. And that's the start of agoraphobia.
A lot of people think agoraphobia is simply "fear of open spaces" but it's not really that simple. In some of the reading I've done it says that usually a panic disorder leads to agoraphobia, because the person becomes frightened of having more panic attacks and so avoids situations in which they might occur...specifically where they can't escape. I believe agoraphobia can manifest without prior panic attacks as well but that's not my personal experience.
I'll also say that my agoraphobia isn't really life-altering or debilitating to any great extent. I know there are people out there who actually can't leave their houses. I've never experienced anything that severe and I hope I never have to, but hopefully my comments are still helpful to you. How severe is the agoraphobia your character suffers from?
For me, a lot of my fear surrounds eating. Eating in public or in front of other people is one of the most difficult things I have to do in my life. For years I would go to restaurants with my family or friends and order nothing, and tell them all I just wasn't hungry. You get a lot of inappropriate comments when you do that, from people you know and from total strangers...like waiters. They'll tease you for "never eating," ask if you're worried about your weight or sometimes even assume you have an eating disorder. The other thing about panic attacks and agoraphobia is that your instinct is to hide it at all costs. So no, I couldn't tell people the truth---that I was terrified of choking, or throwing up, or having a panic attack while in the middle of the meal. That I needed to sit somewhere where I could easily go out the door or to the bathroom if I needed to escape. It took a long time before I was comfortable eating around my friends, and still I struggle. I won't eat around new people, and it's a whole mental-ordeal if I'm in public alone (like say, on lunch break at university).
I honestly don't know why my fear manifests itself around eating, but for some reason that always seems like the best time to have a panic attack these days. But the needing to know where the bathroom/exits are and having a clear path to them is pretty typical of someone with agoraphobia.
If you have any more specific questions I'd be happy to answer them.
