I think your pelvis are tall ,perspective of it a bit off and some of the bottom planes not following the planes correctly. ❤️It's better to simplify the pelvis as a box or half cut sphere and just put the boney landmarks first before getting into more complex form. ❤️Most time it's better keep things simple . We have to get a hang on the simple forms first ( sphere, cylinder, boxes and combination of those forms) ❤️ Boxes are hell of hard for me , but great to get a hang on perspective.