I agree completely with Susie's statement. Please don't beat yourself up. You have taken the time and trouble to come looking for help for your daughter, exactly as a loving, caring, Warrior Mom does.
It is really easy to miss or mis-label sensory issues. My mother (a physiotherapist) AND my father (a PAEDIATRICIAN) both put my sensory issues down to bratty behaviour. It was my grandmother, who had raised eight of her own children and was raising me, who figured out what I needed and how to help me with it.
Be kind to yourself. You're doing great.
Trinity