Congrats. I'd keep the reps on the warmup sets low also. Like 135x5, 185x5, 225x3, 275x3, then a max set with 315x3, for example. If you're gonna do a higher rep all-out set with a lower weight, do it after you've done your heaviest set. And don't be afraid to rest 3-5 minutes between sets. You might need to rest up to 10 minutes after your last set of deads (or squats on leg day) before moving on to another exercise.
