We are really new to the EI world too! My son just qualified last week for 4 hours of speech, 3 hours of OT and 4 hours with the early interventionist. He has a mixed expressive and receptive language disorder, a sensory processing disorder and low muscle tone and he is 20 months old.
It is all really overwhelming! We have been in private speech therapy for about 2 months now because we didn't realize how delayed my DS is and weren't sure he would qualify for EI. His therapist has been awesome about explaining what she is doing and teaching me how to help him at home. I ask every question I can think of and the therapists have all been wonderful in helping me understand. I also found researching his specific conditions helped me understand what was going on in therapy and why.
I had to fight our pedi for a referral for speech, they were completely unconcerned about his development. Needless to say I am in the process of switching.
Its so hard as a first time mom recognizing what is different about our children because we have nothing to compare them to. I thought I just had a quirky toddler but really I have a toddler who is constantly sensory seeking unless I intervene and give him the input he needs.
Good luck with your meeting tomorrow! Remember you are doing everything you can to get help for your DD! Hang in there!