A breakthrough in my healing process

I'm going to call it as it is. I have some childhood trauma that is affecting my marriage. A recent discussion with my husband revealed that my intense fear of all negative yelling comes from the time my mom furiously yelled and cursed at my step-dad when he told her he was divorcing her, and the times my grandparents whom I lived with as a teenager would have shouting matches. I felt very unstable in those instances, like the world was falling apart. I asked my husband, "So it's not normal for someone to freeze in fear when someone is yelling (at a situation, not a person)? And he said, "No. Normally someone might be shocked and concerned, but not terrified." I've told my husband many times that I think yelling is scary. He never yells at me, but he yells when he is in pain or is frustrated by a situation. My automatic response is to freeze or flee, but sometimes I find out afterward that he would have appreciated help. Near the end of our discussion, we agreed that I would get a therapist to help me work through my emotional baggage. My appointment is on October 2nd!