My DD is 12 months and has about 4-5 feeds a day, plus probably that many at night, so similar to yours. She's a big girl too, though I haven't had her weighed for ages - but she's in 18-24 month clothes. I'll step on the scales with her later and come back and update you!
I'm not at all worried about the feeding. Her brothers fed that much at her age, though weren't as big. They're normal size now.
We cosleep. Sleep is important. We usually end up with the boys in the bed too. DD feeds to sleep for most naps too - though now she only has one nap a day, but has to feed to sleep for every night wakening.
Hard to tell how much she eats, because she feeds herself - I put the same type of food on her tray that the boys (4 and 2) have, and she eats as much or as little as she wants. Always seems like she packs plenty away though. I would definitely not be restricting carbs (in healthy forms) for a baby!
I don't for a moment think that she's got any problem. I remember her brothers thinning down a lot when they were toddlers (her middle brother was a v. chubby baby). I haven't seen your DD, but there's nothing in your post that makes me worry about her either. if I were you, I wouldn't be taking the HV's advice.
You could always try reading the Elizabeth Pantley book (No cry Sleep or Sleep no Cry or something with Sleep and Cry in the title!) about how to persuade babies to fall asleep without bf - with no crying involved. I used some of her techniques with DS1 and they worked, though DS2 was rather resistant.
If I were you, I'd tell myself I wouldn't worry about it until she is walking, and think about it again then.