As someone who’s recovered I think you’re #1 priority above building your booty should be unlearning bad habits and bad thoughts. It’s up to you to decide if you think weighing yourself or body checking or counting macros or any of that stuff would get in the way, and to pay attention and stop if you notice it negatively affecting you. Imo it should be health goals first, then aesthetic goals only after you’re definitely in a safe place
You’re still very “small” in general why not keep gaining all around not just the butt? The rest of your body doesn’t really look toned you can work on gains all over your body if you’re done with the booty. Also, don’t worry about the number on the scale worry about how you look/want to look, because the weight isn’t as important as the composition makeup of that weight is- two people can weight exactly the same and look entirely different because of difference in muscle and fat each one has.