I'm 17 and considering implants?

when I shop for bra I can go into the smaller section or women's section.i have aC cup but my ribcage is 29 and fits both 32 or 34s. I've been told that I'm an A or a B by fitters but once I put on an A or B. They even can see I'm way too large for it. My mom is extremely small figured as myself. So I think it's in the family. When I meaasure my s individual it's about a 9. So I'm not a full c but still a C. I'm 91 lbs and 5 feet zero or maybe an inch. For my age I'm normal since I'm 17. I did bmi calculator for kids. But I'm just not sure if it's really worst it. I mean I don't see myself as small really. I can wear push ups and look on the large size. Plus would it be too large for my frame? Help?!