Like the other guy said you are doing what looks to me a stiff-legged/romanian deadlift I see here as the video progresses
1. Set the weight down between reps, dont bounce the weight off the ground but it's a "dead" lift, you should be pulling it from the ground each time
2. Your lower back is rounded before you even start the pull
3. You aren't getting full hip extension at the top
4. Your stance looks too wide, not sure how tall you are but a good starting point is hip width and adjusting as needed from there
Eric Cressey has a bunch of deadlift articles and videos on the web I suggest you take a look at those.
"And for crying out loud. Don't go into the pain cave. I can't stress this enough. Your Totem Animal won't be in there to help you. You'll be on your own. The Pain Cave is for cowards.
Pain is your companion, don't go hide from it."