My daughter isn’t reaching her milestones

Today my daughter had her 9month appointment, my doctor wants me to have a specialist look at her just in case. The reason being is because she isn’t crawling yet, she scoots around all over the house literally from the living room all the way around the kitchen and she also gets into crawling position but kind of just moves back in forth. And she isn’t pulling up on things yet. I didn’t think it was that serious especially the crawling because I am already chasing after her all over the house just by her pulling herself around by her arms. And she stands perfectly fine when I am holding onto her.. anyone else going through this? I am beyond worried