Hmm.. what do you think?

My period was due on the 27th and it has yet to appear.. I took a hpt on Saturday the 31st and it was negative. I'm not sure what is going on. I don't really have any pregnancy symptoms. The only thing going on is my face is breaking out really bad, I'm moosy, irritable, and tired all the time that's it. Could I be pregnant or not likely? When should I test again? Thank ladies