My answer here is based on my experiences as a clinical instructor in the last semester before graduation. So when my students finish with me, they are ready to be precepted as new grad GN/RNs.
I concur with many of the previous posts here, that the manner in which you ask questions probably is causing your preceptors to think you lack independent critical thinking skills. Here is what I tell my students: don't ask me a question that you can easily look up in a source, like what the definition of a word is, or what a medication is. When you have looked up what you can, come to me with questions about things that still don't make sense to you. I expect that they know the evidence-based resources and make use of them. They need to be developing critical thinking. Things are always changing.
Specifically regarding the insulin, I've seen doses from one unit (humalog) to more than 100 units (lantus) and since so many patients on our clinical units either have diabetes or are having blood sugar management, I feel like it's pretty basic knowledge that insulin syringes come in several sizes including 100 unit; insulin dosing is based on so many factors.
I would expect a new grad to double check the dose with the preceptor or another experienced nurse, as 70 units is somewhat unusual; but I want them to already have looked to see what the patient had been getting and what their blood sugars had been running, are they on steroids, that kind of thing that showed they had a basic idea of the relevant things about giving insulin, not just a "Wow, that's a lot!" kind of thing. It looks like insulin, in a 100 unit insulin syringe, up to the 70-unit mark.
Also, personally I would have given the pain medication, then hung the antibiotic (Press-Ganey and all that) but there are other ways to do it too as others mentioned-- have a solid rationale for all of your actions.
I would recommend to you, OP, do some role-playing, practice a more independent learning style, maybe spend some more time in your drug guide and get more familiar with the common medications. Even try videotaping yourself because that can be surprisingly eye-opening. Best wishes!
