Doctor point symptoms and conditions

HI my name is Jennifer, I am 27 years old, I went for my annual check-up on January 9 and I was telling my doctor that I was having headaches and feeling nausea a week before my periods and so she changed me to Loestrin 24 which I hate and yesterday was my last pill Thank God, and so now they switched me to Yaz which I start on Sunday and I am so scared of taking it because I have read so many things about women having horrible side effects such as blood clots in the lungs, acne, weight gain, vision loss and other side effects, I have gotten to the point that I want to call my doc again and get back on ortho tri cyclen but I have not even started Yaz I do not want to seem crazy! Can someone help me cause I am already freaking out and I have not started taking them yet please help!
Jennifer