I disagree somewhat with the tenor of the replies so far. I think it depends on the severity of the thoughts, or how disturbing they are to you. Such thoughts are not completely uncommon, and I don't think they necessarily should be alarming. If you can observe them when they happen, just think about them, without being terribly afraid that you are going to take action, then you might just consider them as strange-but-sometimes-part-of-life.

Whatever.