Maggie,
About 8 months ago the same thing was happening to me. I would wake up and instantly have anxiety/feel anxious. It made things worse because it was like, why am I anxious when I am just waking up and haven't had a chance to even think about my anxiety? I would wake up and feel like everything was "hazy" and it would feel like my heart was pounding. Every morning this would happen and I would get up, even if I still wanted to sleep, and have to clean to get my mind off of the physical symptoms. I would also feel dizzy and nauseated. Luckily I have gotten out of that. I am not even sure when it all stopped but I don't have that feeling in the morning anymore. I know alot of it had to do with the fact that I would be alone in the mornings and afternoons with my son and I would be really scared that something was going to happen to me and no one would know and my son would have to be alone. I worked through the anxiety of being alone and once I got over being scared of that, the anxiety in the mornings seemed to go away. Are you alone at this time? That could be a possible explanation, that you wake up and you are alone and you may not even realize you are thinking this but this triggers the anxiety? Just a reach at something, i guess. Anyway, it can't last forever so you just have to keep working through the anxious thoughts. But trust me, it is easier said than done and I still go through many days of being totally consumed by my anxiety. Good luck with everything and just keep working through it :)