How are you supposed to decide where to get care for emergent conditions? Where is the dividing line between “just book a clinic visit”, “head into urgent care when you get a chance”, and “go inmediately to the ER”?

So this is a question I’ve always struggled with and it makes me feel very dumb especially because I literally am a EMR. This feels like something I should know. But at the same time I have also called to book a clinic visit before and had the scheduler tell me to go to the ER immediately only for it to wind up being nothing.

Certain things are obvious of course. Like if I need stitches or there is other major trauma then I know to go to the ER. If it is something like a concerning infection then I know urgent care can sort me out. For a skin rash that’s probably a clinic visit. If urgent care is closed and it can’t wait then default to the ER. But there are also the issues where I genuinely don’t know on what side of the line they should fall. This is especially an issue for things that have been going on for a while which I know could be severe but almost certainly aren’t.

For example (not asking for medical advice) I’ve been having repeated extended periods of heart palpitations for the past 2 weeks. At first I just chalked it up to screwing up my anxiety med schedule while I was on vacation because my med situation does cause heart palpitations if I screw it up. So I didn’t think much of it at first but now I’ve been back on my meds properly for 2 weeks with no change. So, that’s cardiac symptoms which in a patient would make me tell them to immediately go to the ER just to be safe. But at the same time it’s been going on for 2 weeks and it’s probably just some vitamin deficiency or something so it probably wouldn’t kill me to wait a week for a clinic appointment (no walk in clinic here). Do I split the difference and go to urgent care? It’s like schrodingers medical issue, it’s both the worlds most benign thing and a symptom of immediate death until someone looks into it, so how do I know who should open that schrodingers box?

It seems like there has to be some easy dividing line on how to know which one to go to that I just don’t know.

Edit: In USA, because that probably matters here.