Positive Discipline?

She is 2.5 years old and has not been behaving for the past months. She's been throwing her temper tantrum out of nothing and that is making me really upset. I admit i have been yelling, screaming and spanking her to make her stop but frankly, i dont think this is working. So right now, i am taking some time to read up & understand Celeste better. At least for now, i am going to re-create her night routine. Way to go!