No No and No.
First off, taking time off work shouldn't be done unless it becomes nessary. Doing stuff will help to keep your mind off withdrawal symptoms, it will give you a sense of effiacy and usefulness and research shows if you can stay in work your chances of recovery are much improved. You must reduce your work hours though, even if its only until you are off the drugs.
There is one other option. A week detox program as an inpatient. I am not suggesting it as a good idea but it is a possibility.
Using drugs of abuse to ween off other drugs of abuse is never going to work.
It might be time to consider a Naltrexone taper off the Oxycodone and alternative pain management. Other option is to taper with a benzo. I still think its best to do one at a time.
Drugs for the taper off of the amfetamine could be bupropion, modafinil or a swap to methylphenidate.
Your G.P may not be willing to prescribe the Naltrexone and that might nessitate a referal to specialist drug services. I don't recommend using other opioids for a detox.
Another option is trying a Benzo detox. Although I would recommend adding in a benzo on top of the other options on a PRN basis.
Stop the antidepressant cold turkey, there won't be any withdrawal from such a small dose after such a little time and start on the opioid detox. Once you stop them, never use them again unless its for acute severe pain (like you break a leg), even then, try to manage on something else if possible.
Mindfulness practice daily (meditation in particular), will help with pain, depression and general withdrawal. Alternative pain management can come in the form of Nortriptyline, Amitriptyline, Aspirin, Iboprofen, Pregabalin, Naproxen and Nefopam are all options depending on type, cause and severity of pain (more than likely two to three will be needed to control the pain as well as an opioid but in relatively low dosage).