I have been through numerous medication switch rounds now and even when you are swapped to the right dosage equivalency a lot of it depends on personal body chemistry most of the time.
But i really, really cannot believe your dr has you on all of that medication one for endometriosis, and two such huge amounts of oxy ir for break through pain. the general idea is to make it so the body have less highs and lows, being on such high amounts of an ir drug is going to make your pain worse due to getting a sudden huge dose then crashing, normal practise is to try and keep your pain stable with the extended release. i would try and reduce the ir oxy to get your tolerance down even though you are going to be in a lot of pain for a while it is better in the long run. I try and keep my bt meds as low as possible for this specific reason, and even though my pain is never lower than a 7 i just try and find other ways of managing like meditation, other medication such as nsaids creams that contain pain relief lidocaine patches tens machine etc.
I cold turkeyed all my meds last summer in order to bring my tolerance down (was also on fent patches and ir oxy) and i am glad i did as my condition has deteriorated yet again so i had to go back on opiates but, im coping much better on lower doses even though my pain has yet again increased like it does every winter. im trying spinal cord stimulation next, if that doesnt work i am hoping to raise the funds to travel outside the uk for a course of ketamine infusions.
Im sorry you are in so much pain, i am pretty much housebound with my condition and bedbound for 5 days out of 7 on a good week, but I really would try and reduce your bt med intake and find other methods of pain management because that dose is monstrous.