250CC low-profile silicon. Thoughts? (photo)

Sizing should always be done in consultation with your plastic surgeon. The best results are typically achieved after careful measurements of the breast are performed and the goals are discussed. 
See my video link below for better ideas. 

Thanks for your question and pictures.  Even in a petite young lady like yourself, a 250cc low profile implant seems pretty small.  When I do a breast augmentation consultation, I show before and after pictures of former patients with a similar frame (shoulder width), similar starting point (current breast tissue), and then different size implants in those similar patients.  That allows the patient to make the most educated decision about size.  I would consider a second consultation with your plastic surgeon to further discuss your goals.  Best of luck to you.