The way you are performing deadlits right now is going to lead to back pain / disc herniation. Too much lumbar flexion and an inability to maintain neutral when starting your deadlift. The last day you did deadlifts were a touch better but if you plan on lifting for the rest of your life you're gonna wan to address this ASAP for the sake of your health.
A few pointers that may help
1. Post your videos here --> http://startingstrength.com/resources/forum/forum155/ This is he technique forum. There will be a lot of people who will be happy to also give you feedback. If you only post your videos on your log you may need get immediate feedback.
Safety
2. Don't let your breath out on the way down while holding a heavy load. That breath is what's keeping pressure around your spine. That is a mechanism for injury.
3. If you can lower the deadlift fast - you don't need the eccentric stress to get stronger and your spine is very compromised already. If you need examples you can check out my log I post videos often.
Set up
3. Read read the deadlift section of Starting Strength again in conjunction to watching videos of other people deadlift or better yet from their youtube for visual examples. Here is a great one --> The Deadlift in 5 Steps | On the Platform - YouTube
4. Watch the video form #3 - you need to focus on the cue of Squeezing your chest up/Lifting your chest. You need to do this at least 100% times more than you are doing right now.
5. Here is another video that may be helpful --> https://www.youtube.com/watch?v=Qo803cjyyLU
6. You may be starting too close to the bar. Make sure the bar is position at your mid foot.
Good luck.