Old nurse here.
Take it easy on yourself. I recently heard a new nurse at my hospital say she thought when she got out of school she knew everything. She now knows after a short time that she has had a lot to learn and still does.
At most you have 4 months experience. That is like first year of nursing school
. How competent did you feel then? At present you are just recently off orientation. Time and experience will take care of some of these problems. I don't know if there is an easier field to start out than med-surg. I would think that any critical care,er,etc would be a lot harder because you would have a lot sicker patient where they could circle the drain faster. The learning curve there would be steeper.
Four or 5 patients is NOT a very heavy load. Ours is currently down to 6 from 8. Believe me. Eight was a bear even for experienced nurses.
As for making it through the shift better, I find I need to get to work EARLY to get information on my patients from the computer even before sign in time for work begins. That gives me a running start. I know pertinent labs, meds I have to give etc. I've read on here that some places don't allow this anymore and I realize this is unpaid time but sometime you just have to do what you have to do. It wasn't always like this but now I find it is.
You have to realize that nursing is a continuous learning experience. Medical informaton is growing at an exponential rate. I have more to learn now than I ever did before. You will too. Passing the board simply means you are minimally competent to practice nursing though it has been your goal since the beginning of nursing school. Notice the word minimally. By the time you have a couple of years under your belt and decide to move on from med-surg you will feel better about your skills.
Welcome to the profession.