I agree with others here. It wanted your attention, probably for help – either for a ‘friend’ or for itself. Could it have been a recently fledged juvenile wanting food? It may have seen mom looking for the grass and getting food from that activity, but unable to master the art.
Did you look for a nest or another bird in the original shrub? It could have been trying to keep you from finding an injured friend (killdeer fake wing injuries to lure you away from their nests).
Was it close enough that you can go back with some treats and a camera? I’d do that.
I read the other posts about your relationship with the local birds and now I’m really thinking it is a kid saying, “Mom won’t feed me anymore, but she said you’d do it. I CAN’T!!! Look! I’m TRYING and it doesn’t WORK!”