Chances of getting a positive on a test so soon is very unlikely, even if you think you are having pregnancy symptoms. Unless I'm counting wrong I think you're only on day 12 of your cycle? You may not even have ovulated yet. I'd wait at LEAST another week before testing and even then it might be too soon. You're supposed to wait until around when your next period is due.

With my last cycle I ovulated around day 12 and then it was another 13 days until I got even the slightest faint positive on my test and by then AF was a day late.

Good luck, i hope you get the result you are looking for.