You've got a movement heavy style, but an issue is that you struggle to move linearly. Sometimes it's ok to move straight in then straight out. Especially with your jab. What's difficult about using a style like yours is being able to still punch effectively when moving around that much. You couldn't come back with counters of your own and were way out of position too often. Your best moment is from 5:45 to 5:. You come in straight with a right hand to the body, nice level change and everything. You pull back then circle out right, and hit him with a 1,2,1 as he steps to meet you before disengaging again. That's what your style should be about. Pick him apart with long straight shots, pull back and angle, hit him as he tries to track you down then get out again. Your goal is to fluster him with rangy punches, and run him into power punches when he tries to chase you.
What's missing is fundamental stance. First, as has been pointed out by everyone, you're leaning too far back. But the real key here is you're LEANING back vs shifting back. When you shift back, your knees are bent and your right hip is bent, so your weight is on your back foot but
not on your back heel. You don't want your head past your back foot at any point, just like you don't want it over your front foot. (This type of leaning actually can be effective at making them run into straight punches, but you would need to be switching stances with the steps you were taking and I'm not gonna recommend that to you at this point). So right now you're getting your head out of range, but killing your balance and ability to really do much well by getting your weight on your heels and losing your ability to shift FORWARD again. This is especially problematic when you attack with your right straight to the head, because you're leaning back as you throw it which is gonna get you dropped due to balance if not power if you eat a clean punch at that time.
On top of that, you prefer to move left but I actually like you a lot better moving to your right. When you go left, your foot position is getting screwed up. You're crossing your feet, letting your shoulders get squared up and continuing to lean harder because your upper body isn't properly positioned. Here, look at this:
Look very closely at your left foot. Notice that you've pivoted and swung your rear foot around, but your lead foot is lagging behind that motion. Your shoulders are just squared above you and getting hit right there would be a real problem. If he punched at you, you would be forced to pull your head back (weight on the heels again) until you could adjust that foot and get your balance back. Squaring your foot position when pivoting and when looking to move left in general was a huge flaw, that combined with your leaning made your performance look much more awkward than it had to. Now compare that pivot to this one:
I chose this picture specifically because he's also leaning back. But look at how his foot has already turned into position so the rest of his body is simply following it. Making that motion first means that he can use that lead foot to push his weight back properly when his rear feet swings around and gets under him. It doesn't look like it, but he will be stable and actually ready to change directions immediately after. Whereas when your lead foot lags behind your pivot, your feet end up crossed and you're weight is on the left heel instead of left toe so movement gets compromised. I really think this little adjustment, and working to square yourself up left overall will make a HUGE difference in your game. You'll be able to move left with more balance and thus more defensive/offensive options, that left hook you like to throw as you move will be much better plus you'll be more easily able to go right if you need to. This way you can get your feet moving around your opponents, they won't be able to cut you off (this guy was doing more following than cutting off, so it wasn't an issue) easily and you can't be forced on the defensive looking awkward to the same extent.
In summary, it's ok to move in and out. Get your weight more forward on your feet and keep your head inside your feet. Don't let your left feet get square (don't let it your lead point outside their rear foot, too far to your left) and adjust it first when you pivot. These improvements in your stance and footwork will help a lot I hope.
To put it all together, try this drill: Stand in front of a bag, step in with a jab or 1,2 or whatever, step back and circle around it. Stop, step in again, even feint stepping in, then circle the other way. Keep doing this with the correct footwork and you'll find that you can plant when your opponent gets out of position and hit them with shots, then get out of there again and confuse them. Good luck, congratulations on your win and thanks for sharing!
Edit: Do yourself a favor and study this video. Specifically the padwork at like 9:40. There's a lot in there that can benefit you.
