Ruby, please becareful that you don't mask any pre-existing issues with anti-depressant use. They are a very good tool in a lot of instances, but self checks, friend checks (using them as a mirror to give you a reflective picture) is very important, especially the latter because we often cannot identify our own issues. However, PMT is known to increase and even cause depression, so I think that this anti depressant therapy will be very good for you.
As for the oxycodone, some narcotics have an effect on hormone levels and oxy is one of them. Therefore, going off the pain meds might help that issue. I'm not a doctor or a nurse, so just take what I said with a grain of salt. Also, keep in mind that if your pain is not kept under control it can cause physical health issues, so does the benefit outweigh the cost should be the question reflected over the next 60 to 90 days.
MRI revealed disc bulge and test injections revealed RA. Radio Freq procedures have decreased the severity of pain by about 1/3rd. Was on Nucynta (tapentadol 50mgs) for several months, but due to a decrease in pain, I now used Tylenol #3 with Codeine and .5 mg Klonopin. Go ahead and laugh but the Codeine works well ;)