Is there something wrong?

I'm not sure what to do about TT my 3yo DD. She likes sitting on the toilet and at CC they sit the older kids on the toilet every 2 hours even if they are in nappies. When we are home I do the same thing - she sits on the toilet at regular intervals, even if not 2-hourly to the letter. She has been free to do this and has done for months now.
At home, I let her choose whether she wears nappy or undies - I am trying not to stress out and just let things happen. She has seen me go to the toilet a million times, and usually when she sees me going to the toilet she announces that she has to go, so she goes up to "her toilet".
Here's the thing - she has NEVER, NOT ONCE done a wee or a poo in the toilet. She will sit on the toilet for a good 5 minutes, say she's finished and then within 15 or so minutes she'll have wet her pants. She will tell me when she's wee-ed or pooed but it's almost as though it takes her by surprise when it happens.
How do I explain to her that she needs to relax to let a wee out on the toilet? Or should I just keep waiting for it to happen on it's own? Do you think something is wrong? She is 3 years old... It seems like everyone I speak to with a 3yo girl has told me they have TT quickly and easily. Of course I am sick of her being in nappies, but more importantly I just want to make sure there's nothing wrong...

There is nothing wrong, im sure, it will happen in her own time, your doing the right thing i think and just being relaxed and letting things happen.
With DD i had the same thing so i told her to push rather than relax, since then she seems to have got the hang of it. She will sit there and push and do a wee's and even a poo's sometimes!! I know DD is younger but that doenst mean anything. :)
I really find that nappy off time is helping DD, she will do a little trickle of wee and then either she will stop and anounce wees or i will see and tell her to stop and pop her on the loo. but we had a lot of wee on the floor then it just seemed to start making scence for her!
Another thing we have found that has helped us it to get her a seet for the big toilet. might be worth a try!
Hugs to you

Thanks, mate. Yes, we have a Thomas seat for the toilet that she did love, but that's now soooooo three months ago, LOL! She doesn't use it anymore, just sits on the toilet. Doesn't like the potty much either.
Thanks for sharing your experience. I'm really hoping it starts making sense for my DD soon too.

we have one of those potty's that sing and flush and all that jazz ( a fisher price one) and I find it makes it fun, in a way that only potty's can be! DS prefers it over a toilet! (it's shaped just like on, 'cept it's little)

My friend has one of those singing flashing loos! It wasnt working for her son so she painting it black with a pirate flag and stuff and now he can wait till he has to pee!!! Funny!