Lifting weights,scoliosis, and form?

Hi FBfam! I just completed Day 5 of the FB30 workout which was this video: https://www.fitnessblender.com/videos/build-a-booty-workout-27-minute-butt-and-thigh-workout-for-a-round-lifted-butt-and-great-legs

The last time i did this workout, it felt much harder. When I did it this time around, it was challenging for sure, but it could have been a level 3 in my opinion. I didn't get 'the burn' until the end, with the leg pulses. I am wondering if it has anything to do with my scoliosis? I don't remember how much I lifted last time but I think it might have been slightly heavier than Kelli. This time around I did almost everything exactly the same as Kelli except for the deadlifts. I can't go heavy on them and I have bad form as a result of my scoliosis so that was kind of an uncomfortable that strained my back but didnt really do anything to my legs. However, even the jump squats felt easier, so I don't know if it just because I am a little stronger or I'm doing something wrong. I also went a bit faster than Kelli but stayed at the same number of reps (i.e I would finish a couple seconds before she did). How much does that effect the benefits I would get from the workout?

Another thing I'm wondering is if I have to go heavier next time? I shouldn't really, because it aggravates my spine, but I also want to build bigger glutes and I just don't know what to do. I guess what I, asking is- is it still an effective workout if m legs aren't shaking by the end?

Thank you FBfam for being such an awesome, supportive community- love you guys!