Can I return stretch jeans for being too stretchy?

[Reastie]

Just that really. Have a pair from m and s. previously had two pairs and loved them. This pair was on new this morning and by afternoon was looking very baggy (ultra slim fit so shouldn't be baggy) and droopy. I'm worried if I take it back they'll tell me that's what they all do, but I didn't have the issue wi previous pairs. Got the receipt but for some reason always feel nervous about doing these things