Hi VF,
Spica is spot on. Oxys have strong antidepressant effects, and going off will give a lot of people rebound depression, especially if they were ever depressed before. I also take a mild antidepressant prescribed by my doc that makes most people sleepy, so I take it at bedtime and it helps with that, too.
11 days is too soon to expect to feel better. You've been through some terrible withdrawals with suboxone, so I wouldn't expect you will find oxy withdrawal more than you can tolerate.
A lot of us who choose to reject oxycodone use for pain were originally put on it for that very reason. It's just that oxys quit working as well after awhile, and you need so much to even feel normal, you're toxic before you know it. I have severe osteoarthritis and two artificial knees, and my pain is much less off the oxycodone than it was while taking it. There are lots of docs who will work with you for pain without using narcotics to do it. So work with your doc about that.
You can get through this. I would address the depression if you think it is an issue, because the "miracle drug" that we all thought oxycodone was is difficult to match, probably because our brains were never intended for the dopamine rush that opiates give. It sets the bar too high for what natural endorphins are able to do in the early days off opiates, so give it time.
Good luck, and keep coming back to share how you are doing and get help from all the good posters on this forum.
FT