I've come across many 'old souls' as my manager used to lovingly call them. I have a feeling that dd is one of them too; although we go to many many groups, she, like I had at her age, has spent most of her time around adults.
This is really reflected in the skills she has developed. Her language skills are very advanced for her age; she sounds like she is much like she should be several years older than she is and people are shocked when they are told she is just 3. She knows lots about cue sports and a certain aspect of trance music, due to spending time with dh and her uncle doing their hobbies. She can bake certain cakes measuring ingredents and mixing things in the right order, everything bar putting them in the oven, as she has been baking for church events twice a week or more with me since she was able to hold a spoon. She can make foundation chains using wool and a hook with very little help. Granddad has taught her lots about number and is starting to grasp the concept of very basic adding and taking away; 1/2/3 more or less. She draws and 'writes' with Granny who is in the process of doing a degree and looks up information on the computer about things that intrest her, recently learning scientific terms relating to rainbows and the northen lights! Her aunty and uncle have taught her about the nutrents in foods in great detail and she knows lots about adult exercises thanks to playing personal trainer with them. Her uncle builds things with her to, so she's a pro at organsing flat packs and creating structures out of things, although she finds the lack of screws and nails with her blocks frustrating when she's planned to join them in a paticular way. She's just soaked everything up going about everyday life with the people around her.
But on the other hand she is slightly 'behind' when it comes to other areas. She's only just now becoming truely comfortable with playing alongside her peers and starting to explore playing with someone. She needs more encouragment to engage with groups made up just of her peers, for instance sitting for whole group story time and singing away from adults at the end of some toddler groups.
Like every child in their early years she's learnt what she's lived. Children who for whatever reason have had different expecences have picked up different life skills. So those with older siblings may well be more comfortable around larger groups and there peers, than those who have been mainly with mum, dad, other adults. Those who have been in childcare from an early age may well be more comfortable playing alongside, with, copritively at an earlier age as they've simply had more opportunity. There really is no right or wrong here, and children will develop in the areas they need to when they attend a good nursery or pre-school.
So for dd when she starts nursery/pre-school (planned for september) she'll be learning to interact more with her peers and play with less adult input. To feel comfortable with less adults and more children her age, as she will experience in school. While other children will be developing and improving their language skills, starting to be introduced to the concept of shape, number, colour, etc, learning to concentrate and listen to the adult in charge of them. Early years education is hugely diverse and it's all about good practitioners getting to know the children they are responsable for enabeling them to extend their skills and learning in relation to their intrests.
I fondly remember the almost 2 year old who came to me knowing amazing things about cars and how he learnt to play with the other children in the group using the car mat and a car parking games. How the other children had the opportunity to learn about colour and other ways of catagrising things due to his intrests. And the visit from clasic cars we were able to arrange for all the children.
The little boy a few months off 3 who came to my group to help with the transition pre-school. His mum had been a geography teacher but had taken time out to be at home with him and his dad was in a related area of research. He asked really probing questions, that we'd need to look up the answers to! He was really intrested in the oceans and sea creatures and spent time educating us. We had a marine biologist vist the school we were attached to and give a little talk to my age group who was stumped by the questions he was asking and knowldge he had. He was then taking to the activities for older children run by the person right up to the senior school gcse/as/a level and loved every moment of it.
Or the little girl who loved puzzles, she could sit down an methodically complete puzzles of hunderds of peices. Or when our deputy manager returned to work after her second child was born, putting her eldest in with us who had understanding of number to 50, recognised letters by sound and name, could read simple words, was very able in accademic skills.
I can't recall any of those children ever being board or finding there wasn't anything chalenging. They were learning different and equally as important skills. And when activities aimed more at developing literacy or numeracy or skills they had already mastered it took very little effort to offer an extention of the activiity that chalenged them in that area or another area, like social confidence, that other children needed less or no imput in.
I'm sure your little one will be fine. Health visitors can sometimes be clueless in this area and make unfounded comments if they are of the school of thinking that early education is to teach certain accademic skills. Where others might advise you that certain settings would suit your child more rather than a setting that is purely free play.