17 month old girl

Any advice, my 17 month old is super picky when it comes to food. She doesn’t like trying anything new. Lately I noticed that you can see her ribs and spine and it freaking me out! First time mom! So everything freaks me out! She’s so thin but than again she does run around all day long. But this past couple off weeks I just seen her lose weight not gaining. I’m in the process of finding her a new pediatric since we just moved cities. She weights 24 lbs and in July she weighed 22lbs