My 2 cents:
Start now, use this as a warmup for the next macrocycle. I notive you said you've never done the full lifts so using the rest of this week and a half with lighter weights would be more beneficial to you than trying to go heavier without solid form.
"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."