I'll give some constructive criticism that I hope you will find thought provoking. You say you are a white sash, so I am assuming that is a beginner level in your school, so that is noted.
Firstly, it looks to me like there isn't much power in your punches. This is due to a few things. You comment about speed, snapping the punch back quickly, and whatnot. You need to develop your power first. Fast punches with little power don't do you a lot of good. Heavy, powerful punches that might be a bit slower are a better trade. Figure out how to develop your power first, THEN you can work on speed. Don't develop your speed while sacrificing your power. That's going about it backwards. Keep your power up, and only develop your speed at a rate at which you are able to maintain your power. Keep working on it and gradually your speed will increase without sacrificing your power. It's a process that takes time and a lot of work, it doesn't happen over night so don't get discouraged.
Now, about your punches...different Chinese martial arts develop their power in different ways. They have specific methods that they use in throwing a punch or other strike. Since I don't know specifically what method you are training, I cannot comment on what you should or should not be doing, so I'll only comment on what I see. It looks to me like you are using a generic sort of "western boxing" method of punching. I don't know where that fits in with Chinese martial arts. In my system, it doesn't. I see you are leaning in at the waist when you throw your punches. I realize you are doing that in an attempt to get your body behind the punch, but it's not the best way to go about it. Cutting at the waist like that doesn't give you much power when your feet are not well rooted and braced against the ground. In the wider angle shots, I see your feet floating, your heels are rising, your feet are shuffling around when you punch and they are not flat and braced solidly against the ground. If you brace your feet, then you can actually use the power of your legs to drive your punches, by pushing against the ground. There are specific methods to developing this, and again a proper Chinese method has a specific way of going about it. Because you are not bracing your feet, what is actually happening is that you are only using the strength of your arms and shoulders in throwing your punches. This is never as powerful as when you harness the strength of the whole body, by driving with the feet and legs and up thru the torso.
This is not something that can be adequately explained in an internet forum like this. So hopefully this information will give you something to think about and perhaps have some questions for your sifu to get the specific corrections and guidance so you can improve what you are doing.
good luck to you.
