It was combined... hard to explain but I felt the withdrawal of both and they kind of potentiated each other, the same way taking 2 drugs to get a better high could potentiate each other to equal a whole greater than the sum of its parts, yet you still feel the effects of both.
I've withdrawn from Kratom both before that experience though on its own and also since then again, though with not much of a break, and yeah it wasn't as bad but still bad but before I wasn't taking as much, and withdrawal is probably inevitable if you take it frequently enough, unless you have some very unique body chemistry. Simple advice is: just don't take it everyday if you can help it. If every day, limit it to once a day and in a lower-end dose. Anymore than that and you are probably asking for trouble. But everyone is different. If you find yourself needing it more and more though, I would just stop, and the sooner the better. For me, taking once or maybe twice a day for a month or more and then stopping led to no sleep for several nights, uncomfortable physical symptoms, and anxiety and depression that could definitely compete with actual opiate withdrawal - the physical symptoms didn't subside for 4-5 days and the mental symptoms still persisted mildly after a week, then I would always end up going back. At this point now I'm at 12 days or so and it's the longest I've ever gone without it since first trying it over a year ago. My body is alright but my mind is def still recovering.