Halloween was a disaster

My daughter has been looking forward to Halloween for months and has been playing "trick or treat" with us since Halloween last year. This year, she picked out her costume and we let her pick out our costumes. She has been so excited to trick or treat, but on the actual night it was tantrum after tantrum. The bowl was sitting on someone's porch - tantrum. Someone came to the door before she could ring the doorbell - tantrum. Mommy tried to hold her hand instead of daddy - tantrum. Literally at one house she told the woman she didn't want the candy after 3 agonizing minutes of the nice woman offering it to her. We finally gave up and went home with her screaming the whole way. It was embarrassing. I don't understand what went wrong and I'm too beat down from other meltdowns to try and problem solve. Has anyone else experienced anything like this? Were our expectations too high for a 3.5yo?