Dont make since..

I was supposed to start my cycle today, but she decided not to show her face. I got a dollar store test it came up big fat negative. I have always had my period on time and always early when it comes to glow. So I'm a little worried. I've had all the symptoms of a period, the gas, the poops, the mood swings, lower back and thigh aches, migraines, sweet tooth, but no period...