I agree with Sasfooty. There's no substitute for your own ear and your own judgment. Nobody knows better than you do what you heard. You're the one who understands the context of whatever it was you heard. You're the one who has been in that same place over time and knows what's "normal" for that space, and what is not.
We teach ourselves about the origins of different sounds, by listening to our own recordings over and over (if you're a person who makes recordings), and by placing ourselves in the field (or our own backyards) over and over and over, and finding out what happens there. The learning you do that way is more valuable than anything any "expert" could ever tell you.
I don't know much about the woods, but I know a lot about learning, because I've been doing it every day since the day I was born, just like every human being has. Each of us has inside us that special machinery that allows us to learn whatever we want to. All we have to do is decide what it is we want to learn about, and then focus our attention there. Through that focus, learning happens.
As I say, when I started going to the woods to learn about the people who live there, I didn't know anything about the woods. But I listen to the sounds as closely as my bad hearing allows, and I can detect patterns and note variations and compare things, just like the "experts" do, and I do that by using the standard-issue equipment we all have: our ears and our brains.
One evening, while sitting in one spot in the woods, I heard a sound that seemed completely natural and unremarkable, so I completely disregarded it, and my mind wandered to other things. After a while, I became aware that the sound was recurring. It was a "natural" sound, but its frequency (and loudness) started to seem a little odd. Then I started singing, and I noticed that the sounds would stop while I was singing, and start up again when I stopped singing. Finally, I began talking directly to my invisible audience. When I finished singing, I said out loud, "Well, that's it for the night; I've really enjoyed singing for you." The instant I stopped talking, I heard a thunderous "whack": The sound of wood on wood.
In that moment, I finally understood all the sounds I'd been hearing for the previous hour or so. Those "natural sounds" I'd been hearing had been coming from a hairy person (or persons?) who were trying to make contact in a gradual, non-threatening, non-scary way. But I was completely oblivious at first. It was only over time that I started to recognize the significance of what I was hearing. I taught myself, over time, what those sounds meant, simply by staying in one place, listening, and staying alert.
Please notice that I said I disregarded the "natural sound" when I first heard it. Even though I had had interactions with BF before this point, I didn't leap to a conclusion about what I was hearing, the instant I heard it. I had to learn what I was hearing. I went through a learning process in that half hour or hour I spent in the woods that day.
Of course, some learning requires a lot more time than that particular piece of learning did. But learning always follows the same basic trajectory. We start at zero (or close to it), have some experiences, and then through those experiences, acquire wisdom. Trust that process, and trust yourself, and trust both those things above the words of others.