A few years back my SA was like this, I went to school I would sit in my class room for the entire day and then go home. I had all my classes in one classroom fortunately for me. Occasionally I would go to the bathroom, not because I needed it, but because I didn't want people to notice that I never left the room. I would stand in the bathroom and count the minutes, wash my hands and go back. My "friend" who was always noticing out loud everything he thought was weird about me asked me why I was always there. I can't remember what I said. Sometimes I would skip school cause I just couldn't go, I would keep close attention to how much attendance I had in my classes and how many classes i could skip without failing the course. I couldn't bear explaining my absence so I kept within the boundaries. My parents didn't like if I stayed at home, so I would try and get myself sick, for a better reason. I remember that I sat outside our back door in the middle of the night in my pajamas in the snow. I sat there as long as I could, and was freezing when I went inside. I tried eating sweets too to weaken my immune system.. that't the only thing I thought of.
My sister is married to a psychiatrist and they helped me through my roughest times. A year or more after i was done with that school... and after working on my SA quite a bit, I went alone to the US to attend a 3 month seminar (i'm from Europe). I had never traveled alone anywhere. After all of that I can give speeches, teach classes, and all sorts of things.
I know that sounds like I don't have SA, but although I have gotten better in many areas, I still have some stuff I need to deal with. Like intimacy problems with people.. and i've had a setback because of some stuff. But I know that it's possible... I just wanted to share that. And I liked what my brother in law said once. He said, "you'll never be the same and experience the same problems" and he's right, i have learned from my past problems and now I just have to learn the other one's away!