DD says her chest hurts if she runs

[paranoidmother]

DD has been to a sleep over last night for a birthday, so Pizza, cake, sweets etc have been eaten and little sleep had. It was an 8th Birthday.

DD has come home and not done much but played a bit and then watched some TV, def. going to need an early night.

Kicked both kids out to play in the garden and asked DD to do some running around, at which point she started to complain that it hurt her chest when she runs. It's not done this before and she's not complained about it before.

She says it only started last night at friends house but there wasn't time to tell the mum about it. She says it really aches but apart from when asked to run you wouldn't tell any difference in her.

At the moment I've told her to go an have a nap as she hasn't had much sleep. Also explained that she's unfit as well as she does complain about walking anywhere etc. However she's not over weight, eats plenty of veg etc and runs around perfectly fine at school and if we go to the park.

Can something like this (not sure what this is) just happen? Could it be too many party foods?
Am I paranoid? Should I see how she is in an hour or over the weekend?
Is DD possibly trying to get one over on us to get out of being outside? (She's done this before)

Any ideas or things to do to test anything or recommendations would be gratefully received.

Thanks

I have asthma and that's how it was diagnosed - when I was a kid, my chest hurt when I ran around.
Maybe take her to OOh?

Was she doing any activities yesterday?

Dd had pain in her chest last year, it turned out to be a pulled muscle from martial arts.

Thank you.
She's had a nap and is no outside running around playing football. She did have asthma as a baby for about 5 months but dr said she was fine now.
I'm going to make an appointment with Dr just to be on safe side and also monitor her to see if anything sets it off.
I can only imagine messing around with three others yesterday might have done it or today.

Thank you