Sensory processing disorder?

How to tell the difference between it and stubbornness. Ive made an apt with my daughters doctor but i cant get in for 2 weeks. And as ive been googleing i think this has been what has been whats going on for so long. She is 6 and throws a fit over getting in the bath, wearing anything but running shorts and shoes. In the winter i can get her to wear leggings some but she cant stand pants not past the ankle and shirts not past the wrist.she will not let me help her put her shoes on but will not do it herself until im late for work. She will not get in the car i have to put her in screaming. If i sign her out of school and grab her backpack she sits down and wont leave angry that she didnt get to sign her name and grab her own backpack. Morning are awful and im at my witz in she wont get ready but wont let me get her ready either!