Breast Cyst

A couple days ago I noticed a lump in my breast. I immediately went to see a doctor. He told me that it was a cyst and that I would need to have it looked at. He scheduled me an appointment with a specialist on the 23rd. My question to you is, should I worry? He told me it's nothing to worry about but I can't help but worry. Has anyone had this problem before. What was the outcome?