What Causes Dizziness, Hot Head And Burping Before Periods?

right before my monthly period i feel light headed, hot head, cant think straight, need to go to the bathroom! anxity last for about a half hour then goes away if i drink alot of water at that time i have to go tothe bathroom right away! sometimes get the burping and need to move my bowels i have been to a doctor for blood work, ekg even seen my gyno and she said it is my hormones! i even went to the hospital, this has been happening ever since i had my children about yrs now! and it is very scary