You feel guilty because from the first day of our education nurses have the message "you are responsible" hammered into us.
Now sure, we really are responsible for a lot, and ought to be - I firmly agree that we ought not practice outside our range of competence, for example, and of course we have a host of duties regarding self-education and safe practice and patient care.
However, we also find ourselves answerable for things that aren't within our control: patient outcomes, doctors who leave bed rails down, a cleaner not posting that the floor's wet, rates of MRSA on the ward, allied health and medical discharge planning, doctors not calling in ICU fast enough on an unwell patient, the previous shift not ordering staff, and making sure the family don't feed a nil orally patient. These come to mind from my last four shifts - all things my colleagues and I have no control over, but were somehow still responsible for.
This is especially the case with sick leave - ever-present in this is the idea that, although we do not generally feel valued by admin, we are irreplaceable. Without us our patients will suffer, our colleagues will have be laden with an untenable burden, and our selfishness will blow the budget. We expect things of ourselves (and each other) that we would never expect of our patients! I can't tell you the number of patients who've been told of for bringing in laptops or conducting business on the phone because 'you're sick and you need a break'. But you? Standing in a pool of vomit, dizzy from dehydration and being ill? Just pull an IV pole around with you and you'll be fine!
I'm sorry - I seem to have hijacked your thread with my own little rant! My point is that if you're sick you need to rest. If you're sick enough that IV fluids are even being joked about, you need at the least to be home in bed resting.
Repeat after me:
Although I am awesome, I am not indispensible
My health is as important as the health of my patients
A sick nurse cannot be an effective nurse
Slow sips of flat lemonade and a dry cracker
Feel better soon