PMS symptoms are extremely variable, and almost every symptom has been described. I do suggest checking in with your regular doctor because the symptoms are severe enough to cause you anxiety. If they are menstrual-related, they might be alleviated by a medication such as Sarafem which is approved for treatment of PMS.
It might be helpful for your doctor if you keep a symptom diary documenting which symptoms are worse on which days of the cycle--sometimes there is an obvious relationship to the cycle, and other times it turns out there is not--this can be very helpful diagnostic information.
Whatever the case, worrying excessively will only make matters worse, so stay calm while you are collecting the information prior to your visit.