I'm getting a breast reduction soon and am very nervous, I have questions about the procedure?

So I'm 14 and have extremely large breasts. I've been trying to get approved for this surgery since I recently turned 13 because of many struggles I deal with because of these. My mom was telling me stuff like "You'll lose feeling in your breasts" and I'm honestly not sure what that means? And I'm very nervous about dying or something going wrong during surgery? What are the worst things that could happen during this and should I really be this worried? I've never gotten surgery before.