What Causes Light Periods With Throwing Up?

Hi im 22 years old and i always have normal periods and they tend to soak up a pad but this time around its super light and only when i wipe myself do i have bright red watery blood a week before my period was due i was having mild cramps and nausea and some throwing up and now that my period is here im still throwing up i really dont know whats wrong can you help me