Unable to decide whether to submit the work to conference or journal. Possible mood switches before deadline and how to deal with it?
If your paper is ready to go and in good shape for a high-impact conference, I would recommend sticking with the conference.

The reasons that I would suggest doing so are:


In many subfields of Computer Science, a highly competitive conference publication is often effectively worth more than a journal publication.
The conference deadline is now. If it doesn't get into the conference, you can always choose to send it to a journal later.
If it's well received and/or you get interesting feedback from the reviewers or audience, you might end up changing your mind about whether to submit an extended version to a journal. You can't change your mind in the other direction.