I love the "careful" adjective because it is such a minute yet powerful detail. The mystery surrounding this poem is effective. Have you considered adding a line or two after your second line in the first stanza. As the reader, I wonder why this day did you finally write a poem for your mother? Were you reminiscing? Did it suddenly dawn on you of your vital yet complicated dependence upon your mother? Did you as the speaker know this poem would affect your mother so?