My DD is big too - though now at 2.9 her weight is starting to level off, she is still extremely tall for her age. She is absolutely fine, very bonny and healthy, and very steady on her feet.
I haven't seen the HV for ages, but when DD was younger I was often given the third degree about what I was feeding her, and I don't think they believed me that I was exclusively breastfeeding and not giving her gallons of formula. They don't seem to take height into account, and just assume that if a child is heavy that means that they will become obese. DD isn't fat though, just average build but very tall!
Like LoveAngel we struggle a bit with other parents and children assuming DD is older. She always gravitates towards children the same size as her when we're out and about, they are usually a year or two older than her so are very puzzled by her behaviour and the way she talks! She doesn't understand waiting, or that sometimes other children don't want to play - so I get funny looks from other parents quite often, and I am constantly having to explain that she's only 2.
I do worry about her, especially as she is due to start pre-school next term, but I try and keep it all in perspective - after all, she is healthy and happy, and that is what matters.