You have picked three excellent poems to look at! What is particularly interesting about the poems you have selected is the way that they do offer very different views of Dickinson's life. For example, if we look at "I'm nobody! Who are you?" we can see how Dickinson deliberately classed herself as a "Nobody" and saw this as a much more advantageous identity to possess than the "somebodys" who are compared to frogs who "sing the live-long June" and constantly have to shout out who they are and why they are important to be a "somebody." We get the impression from this poem that Dickinson is a character who deliberately courts solitude and being unknown and is satisfied with her talents going unrecognised, as they largely were in her life.
However, in "My Life had stood--a Loaded Gun," the exact opposite view is presented as Dickinson imagines her life to be like a loaded gun which has never had a chance to fire and shoot. The images of suppressed violence and rage, as the speaker delights in having "the power to kill." Obscurity is something that in this poem is hated and rejected, as the speaker loves being used to kill and to shoot.
Lastly, your final poem, "Wild Nights! Wild Nights!" again offers a slightly different image of Dickinson, especially given the clearly sexual implications of the reunion of the speaker with her beloved. In particular, her desire to "moor--In Thee" in the final line is an explicitly sexual image that makes us radically reasses the life of the tired and reclusive old spinster that we imagine Dickinson led.
The three poems therefore each offer different and contradictory images of Dickinson's life, forcing us to reassess our own opinions of her and proving she was a much more complex figure than we ever could have imagined.