This sounds very similar to a situation I observed closely and was peripherally involved in.
Since I have not heard anything egregious, my bet on this (diagnosis, if you will) is "Failure to reassure."
Think about that. Being introverted is one thing; many people consider themselves such. But when you are new to those around you, new to the setting, new to the profession, etc., you certainly can fail from "failure to reassure."
It goes like this: Someone is inexperienced. They are prone to run-of-the-mill, not-too-disturbing ignorance and misunderstandings, like I did when I was brand-spanking new on orientation and thought that medication was to be removed from an ampule with a regular needle and then pushed into the IV line through a filter needle. In my case I asked a question (is it this way, a, or this way, b?) and got the correct answer and none of this affected a patient. But when people don't talk and want to get by on this idea that "I'm thinking though things, I just don't say it out loud" - there is no way for others to know that.
There are a lot of things that can act as pitfalls for new nurses, but one of the surest is a staunch, somewhat defensive determination to use introvert status as an excuse for lack of appropriate and necessary communication. Uncomfortable though it may be (for some more than others), this stage of your career requires a great deal of interaction.
Secondly, given the situations described, introversion/lack of communication often also affects other areas, such as the idea of being pleasantly assertive/asserting yourself in your patients' best interests (and your own).
The reason I think your lack of communication is the problem is because you haven't mentioned anything else that most new grads aren't prone to - and are usually easily coached through. On any given day they may struggle to catheterize someone, can't perfectly judge urgency vs. non-urgent vs. emergent, and might upset a nursing assistant by not immediately evaluating someone's chronic problem. In order to be coached, they simply cannot stay in their own world inside their own head.
Introversion will fail as an excuse for lack of necessary communication. You can teach yourself improved interpersonal skills.
Best of luck ~
