I've got something similar to that; I don't vomit or anything, but I get particularly anxious right before a vacation of any sort. Generally, my anxiety centers around questions like "will I get everything done before the break ends", etc, even if I don't have anything particularly important to do. It can be over something as trival as sorting laundry- "aack, will I get all my clothes folded???" (follwed by all sorts of horrible feelings). This is a realization that I've just come to recently. This knowledge itself has helped me tremendously, as I can now center my efforts on making sure everything important is done and then calm myself a bit by knowing that I have nothing important to do. Something that seems a bit cheesy but has worked for me is aromatherapy. The smell of lavandar is very soothing, and for some reason it helps to give me just a bit more control over my thinking. I have a bottle of lavandar oil which I will sprinke on my pillow or in a bath before bedtime. Also, lavander mixed with almond oil is nice for rubbing on your skin. Of course, this could be a placebo, but, hey, it works for me!