I am glad you are trying to get in to see your physician, it is important to be evaluated in person.
Any woman who is sexually active who is not using birth control should consider the possibility of pregnancy. A few of your symptoms are common signs of pregnancy (fatigue, breast tenderness and swelling, and nausea).
If you are not pregnant, changes in your menstrual cycle can signal hormonal shifts and often imbalances. Tracking your cycle and other symptoms over the next few months and sharing your findings with your doctor can help you both figure out what is going on.