I've been acting for a long time, so I'm gonna pass down some things I've learned throughout my years:
Pay attention to your movements when you're doing monologues (or any acting). I had a tough time paying attention to what you were saying because of how your feet were moving around so much. You were also a bit fidgety with your hands. You want your whole body to reflect your words, as body language speaks volumes.
Also, since you're clearly interacting with your mother in the monologue, it feels a bit weird to not be able to see her. Maybe if you made it more clear that you're on the phone with her or something - that way it doesn't seem like the audience is missing half of what's being said. If you add another actor, then it's no longer a monologue.
Last thing (and it's a generality): always be your character. Whoever you're playing, you need to become that person, and put the "you" that you actually are aside completely. Who is this character and why is she saying these things? What is she hoping to get out of the conversation? Think about what kind of relationship she has with her mother, as well as her boyfriend. Give your character background (even if there is none provided by a script). It'll help you to be more convincing with what you're saying and how you're portraying yourself.
Hope that wasn't too blunt/abrasive. You're on the right track, so keep at it!