Hi, Cam! The Yoneda Lemma is dead easy if you think about it the right way: it's a way of making precise the intuition that everything only is itself by virtue of its relation to other things. However, it seems to require a guru to really explain this!
I could explain it... but unfortunately it seems not to be discussed in _[Seven Sketches of Compositionality](https://arxiv.org/abs/1803.05316)_. We'll probably have our hands full - for a while - covering that book. So, you'll learn about sheaves, topoi, monoidal categories and other awesome things, but not Yoneda. Not right away.
I've had little luck getting non-category-theorists to learn category theory from Lawvere and Schanuel's _Conceptual Mathematics_, even though it seems charmingly simple and direct to me. Maybe it doesn't lead the readers through enough grubby calculations... maybe it's too slick to even register as mathematics to most people! I don't know, but we have to learn by experience to figure out what works.
Sounds like you're doing cool computer stuff. You will at least meet other interesting people here, even if Yoneda remains beyond reach.