Do not, DO NOT bend at the waist when deadlifting. Assuming you like being able to walk and move around without assistance.
What you are doing is perfectly normal and fine. However, you do want to adjust your form so your ass doesn't have to come up first, in other words experiment with how high or low your ass is till you find the height that you can pull the most weight with. If your ass is coming up first, you're just wasting energy.
I'd need a video to be absolutely sure, but this sounds reasonable.