S.B.
My friend's little granddaughter does this. She's 5, but she does it every time we visit. It's just for attention. She really likes my son who is her sister's good friend. He's 15 and doesn't always know how to take her when she just walks up to him and stares and then flings herself on the floor like she "tripped". She's just begging for his attention. Last night she had her grandma's high heels on and was dramatically falling down. Once I mentioned her pretty shoes, she all the sudden quit "falling".
It's pretty normal behavior both for boys and for girls.
You can just try ignoring it.
Like I said, in the case last night, the little girl was just dying for someone to notice she had grandma's shoes on. That's all it took. For THAT night.
Guaranteed she will flop and fall over next time we visit. It's a way of showing off.
Little kids can be so dramatic and it's actually funny sometimes.
I wouldn't worry too much.
Best wishes.