Definitely. . . lots of what's been shared here are what I would hope to see in a new-grad/orientee nurse. Being eager to get all of the "task-stuff" out of the way (learned, practiced and competent) is a first step.
For me, though. . . being willing to "dig deeper" into the roles of the Professional Nurse is a pleasure to see, too. "Teacher". "Advocate". "Preceptor". "Care-Giver". "Forever Learner". "Problem-Solver". "Critical Thinker". "Team-Player". "Team-Leader". "Role Model". "Researcher". etc., etc.
Well. . . maybe not all. . . and certainly not all at once, but, at least to my eyes, these are the "roles" of the Professional Nurse that go along way to making the career satisfying, challenging, effective and life-long.
Learn what you need to learn to draw that blood lab. Now, that you can do that, what are you going to do when the potassium level is 2.5 or 7.9? If the situation presents itself appropriately, what and how are you going to teach your patient to keep the potassium level within normal limits??
Be patient with yourself. Mistakes will come. As others have said, learn from them. Then, move forward and appreciate the growth as you continue to learn, practice, master. . . and teach. :)