Am I Pregnant😱😩

I've never been late before and my period still haven't came and I'm scared that I might be pregnant but people say you should wait 2 weeks for your period but honestly that doesn't makes sense because if you're a regular like me you would assume to start on the days you likely know you will start on. So why all of a sudden I didn't start on that day that it's suppose to start ? And the most weird thing is that I've been having pain but no period. I also already took a pregnancy test 5 days before my period was suppose to start and it came back negative do you think I took it too early ?Â