To the OP,
The refresher course seems like it would be a plus to an employer. You'll want to put some thought into explaining the gap between graduation and your next job interview
, too. I don't think i'd even mention that quickie job thing you once had, at all, since it ws so so so short that you didn't even finish orientation. The abrupt departure there, might cast a negative light on you to an employer.
I agree with the person above who thinks that you might need more experience to go into public health, but, worth a try, if there is a setting where you would have a mentor, or some support system of other coworkers around you, to show you the ropes.
I think, if it is autonomy
you prefer, you might be happier doing home care, or hospice, or private duty. In most of those situations, you have few if any coworkers around. but, this requires enough experience or confidence to feel comfortable on your own, too. Some home care is done house to house to house,
sometimes, you work an entire shift in someone's home. There is both pediatric and adult home care, too. Typically, each and every home you go to for shift work,
would provide it's very own orientation to that particular home, to that particular patient.
EAch home case is different, but, generally, this is often very 'easy going' type of nursing, laid back, low stress work.
On the downside, it can be boring, not a lot of chance for advancement or learning new things, etc,
but, pretty laid back job if that would suit you.
Re: the mood, if you do struggle with a tendency for depression, perhaps talking to a private counselor might help you get to the root of it?