She sounds perfectly normal to me I have one on both ends of the scale. I had a baby who didn't talk until almost 2, didn't walk until 14 months, didn't crawl until 11 months and would happily play by himself in his own little world all day and never threw a tantrum until he was 4.
Then I had the early walker at 8.5 months, crawled at 4.5 months, first word was at 5 months, and was talking in sentences at 12 months "i want bottle" "yucky poos" etc. and could write his name before he was 2.
Neither of them are abnormal in any way to me, both fall on the scale of normal for all their developmental milestones, as does your little miss. Even though she is advanced for MOST children her age, she is still well within normal
ADD/ADHD is over diagnosed. I have seen children with it, my sister, and a close friends child were bad. Then others who are normal, and people label them which is wrong. I have taken dexamphetamine (sp) which is what they gave my sister and friends child to treat their add, and let me say if you took it you would mellow out too. It's not a nice feeling. THAT is why I think a lot of the time, people give their children these drugs and see an improvement (going quiet, sitting still etc) because it would have that effect on most people, feeling drugged out (I did).

I don't know how this would affect us if the midwife is right. I'm not sure what to do or what to think, or how to feel.
It shouldn't change anything about how you feel hun. You have looked after your daughter fine until now, why should a label like ADD/ADHD effect that?

I would say that she is under stimulated. By her age Chase was almost writing his name, and knew many books off by heart. Maybe try challenging her mind? Teach her to do things that most don't start till later.
Also it could be food related. A LOT of children have reactions to foods, a big one in this house is yellow food dye, so things like twisties are a BIG no no. Doesn't mean they have ADHD.