Is there an exact difference between non-monogamy and polyamory? Or do the two have to go hand in hand? Or is it person by person? Because I think I'm non-monogamous, but I don't exactly know if I'm poly..
Non-monogamy is a very broad category can take many forms; polyamory is simply one general sub-category that encompasses a certain range of behaviors and configurations. Relationship anarchy, swinging, cheating, single-and-dating, and even serial monogamy can be considered forms of non-monogamy depending on how you’re defining “monogamy” in the first place.
Here’s a very brief (and not necessarily inclusive or all the different ways one can engage in non-monogamous relationships) summary from Psychology Today that offers some general definitions, but there is much more information to be gathered from across the interwebs as well as in print books (Tristan Taormino’s Opening Up might be a good place to start). It’s also worth pointing out that people will often define and carry out their relationships in ways that may not line up with any other person’s strict definition of a term.
I might suggest focusing less on whether you think you’re poly per se (I’ve heard multiple points of view on whether poly is something you “are” or whether it’s something you “do”–neither my wife nor I identify primarily as poly, though for rather different reasons; however, the way we carry out our relationships is often analogous to how many poly-identified folks do theirs), but rather looking at what your more specific relationship needs/wants are and what kinds of relationship arrangements or dynamics might fit your needs. There are probably as many different ways to do non-monogamy as there are people, and it’s OK if your relationship needs don’t line up with the mainstream definition of any particular umbrella term.