How do I fix oversupply without block feeding?? Is it possible?

Since birth, I’ve been offering both sides for at least 15 mins (or for how ever long she wanted to nurse for on the second breast) because that’s what I was told at the hospital.

I THINK my supply is well established by now, my daughter will be 6 weeks tomorrow. But I’m still hesitant to try block feeding, which I’ve been told can help with oversupply.

I’m always engorged and she continuously has green poops. She also has become very gassy and spits up frequently after eating.

Last night she screamed for 20 mins until we could get her to burp and poop. I felt so bad and I don’t know what to do to help her out since I don’t know a lot about breastfeeding.