Well ... I wont comment on your strokes as they are better than mine. I will say that as far as NTRP range that is hard to judge without seeing match play.
I will say that I am a 4.5 and I would not be scared of you in a doubles match based on what I see. In your rally shots you simply dont move your feet. I have 100 pounds on you and I still move my feet to hit balls occasionally. And the one volley we see would scare no one. Perhaps in singles being young and quick (which all young people are aren't they?) would help you considerably.
So if you were playing doubles exclusively I would say no higher than 3.5. But you could be as high as a 4.0 in singles provided your quickness made up for other deficiencies.
"You should be playing linebacker, not singles."