jessia - hi, just found this!
yes, she sounds exactly like my dd., who is the same age (6.5) until we moved to the US 18 months ago, i was a teacher, so had lots of training for ADhD, and have been convinced since she was 3/4 years old, that she was heading this way.
diagnosis isn't made til about now, as 'fidgeting' and lack of concentration describes most kids age 4. BUT I could see the difference between dd & her peers. Because of the move, she has had 4 teachers in 3 years of school, all of them said the same thing - she is slightly higher than usual for impulse control & activity.
kids with ADHD have brains which work differently. if they are just vv active, the meds won't work, if they are ADHD, the meds usually do (once you get the right prescription).
don't know where you are, but we went to the gp, got a referral to a paed. we then had to fill in forms (one of them is the Connors Form - Google it, there's loads of articles)
Generally, if the same behaviour is evident across a range of both time and situation, then it is considered ADHD possible. It's if they are only 'naughty' in one place, then it's thought to be them choosing that behaviour. Hope that makes sense?
sometimes fidgeting is due to other things - we have to give dd iron as well, as she was low on that, and it makes legs 'itchy' so didn't help.
with dd, we were told, it could be that she's just upset by the relocation, or that she's just fidgety, or that she's ADHD, or that she'll just grow out of it, so v hard to tell at this age - it's only as they grow older that you really know if they need med for long term.
we are also under doc's orders to do LOTS of activities, arrange play dates etc. I would just talk to the teacher first - one ballet teacher reduced us both to tears by saying that dd was 'uncontrollable' and banning her for being too jumpy. dd does NOT do well in big group things, like football/soccer, but a fun dance class, swim instructors who cope well with her jumping around, play places with a few friends, these all work well.
I am new to all this - there are loads of people here with a lot more knowledge, so don't just rely on me.
There's a huge number of websites about ADHD, so plenty of info to absorb.
Good luck