Almost intolerable

My anxiety level has become almost intolerable. I say almost because I am still sitting here, tolerating it, but I very nearly can't take it anymore. My anxiety level has been out of whack for the past few weeks. Before I felt relatively anxiety-free - now, it's through the roof. It's a 15 out of 10. I am physically feeling it which I don't always when I have anxiety. It feels like it is making me physically sick. It's not the OCD kind of anxiety. I didn't even unplug the lamps (I am going out of town today). It's something else. Like an impending sense of doom or something of the sort. Like something bad is going to happen and I don't know what. And to make matters worse, I have to get on a plane today. Now I don't have a huge fear of flying in general, but today, it is making me anxious. I feel so anxious I feel sick. I don't know what to do - I can't figure out what is causing it.