Twing Lower Back Strain Deadlift

The title doesnt make sense sorry about that. I was 2 weeks away from starting my 12 week power lifting cycle, my very first power meet. I was sumo dead lifting about 445lb when on the first rep I felt a twing or snap in my lower back left side. It hurt when I walked, hurt like hell when I bent over. I was pretty much lying on my back for 2 days.

Alot of heat pad and alot of pain reliever. A week after the injury I realized that it is definitely not a muscle pull but could be a ligament or something.

( 7 days out from injury) I dead lifted yesterday 225 lb for about 5x4. light stuff and it felt okay. I am extremely disappointing because this was my first meet and I really wanted to hit some good numbers even for a newbie like myself. My plan was to hit 500lb deadlift, 400 squat, and 380 bench @ 165. Becasuse I am so afraid of re injuring my back I may attempt 400lb dead lift, 315 squat, and bench 380lb. I still would love to compete and put some numbers up even if I dont place. Pushing it any harder honestly scares the shit out of me because ive never been hurt like this before.

I think it happened because when I went down to grip the bar, I grabbed it with my left and first applied some tension to bar and then grabbed it with my right hand to start the pull. I think this may have created some sort of imbalance and rotation. Usually I always grab the bar with both hands at the same time but on this day I did something different I dont know why.

I was wondering if anyone had this type of injury and how you recovered from it, and also what are your thoughts on the numbers I should be hitting for the meet 13 weeks away. I would really appreciate the advice. Thank You