I did some competing in both powerlifting and weightlifting (“Olympic lifting”) but it’s been a number of years. After a powerlifting meet, expect to be fried for about a week and you’ll probably want to take that time completely off from any training or significant physical stress. Your CNS is completely cooked after that kind of effort.
The other aspect that is difficult about powerlifting meets is managing the downtime, be it quit a bit or almost none depending on how much competition there is in your weight class. You may end up waiting hours between lifts, or just a few minutes and I’ve seen people having as little as 1 minute between their 3 attempts due to being the only person in their weight class.