Short anwer to your question: yes.

Long answer: I might be off-base, but I think what you really want to know is if these violent thoughts are a sign of anxiety, or if they point to some kind of disturbing personality flaw inside yourself. I'm happy to report that, from what you are describing, your hunch that these are "intrusive thoughts" is the right one.

Recently there has been some research on what are called "anger attacks", which are actually a variant on anxiety attacks. Instead of feeling anxious, the person feels the urge to cause violence in just the way you describe it. I know this because I've been through the same thing...many times. My attacks don't go on as long as yours, but I know exactly the feelings you are describing.

Here is a link to an article about anger attacks. For some reason About.com got rid of this page, so I have to give you the cached Google version:

http://72.14.205.104/search?q=cache:qWdHQrqs2KUJanicdisorder.about.com/cs/pdbeyond/a/angerattacks.htm+anger+attacks&hl=en&ct=clnk&cd=1&gl=ca

For help, you might want to click on the Anger Management link that follows the article. That's not to say you have an anger problem, but the pointers they give in that article have helped me out.

Also, make sure you start seeing a doctor at your college on a regular basis, as you seem to be planning to. Right now I'm on a 2.0mg/day dosage of clonozepam, which seems to keep these anger attacks in check. I'm not trying to offer you a perscription, but what I am saying is that help is available if you go looking for it.

Good luck.