Strain all day?

[Asparagus and Lemons]

DD has been doing that straining sound, like she has wind, ALL day! I have been burping her lots and I dont think its that anymore.
Is there anything else that could possibly be making her doing this straining noise? Its driving me insane. She's not crying any more than usual. And shes been doing plenty of explosive poo's, so no problem there.
TIA

[Mad Scientist]

Could it be that she's just experimenting with sounds? My DD1 used to do a weird sound when she was little and people always thought she was pooing but she was just making the noise for no reason. She stopped eventually. Sorry probably not much help...:s