(This is a copy and paste answer from my first reply. I replied 8 minutes ago per my clock)
My name is***** and I am sorry to hear that your kitty is feeling so poorly this evening. While I can really understand that you want to help make your kitty more comfortable this evening, I don't this oxycodone is a good idea for her. Cats and strong narcotics don't mix well together and cats can often get INTENSE dysphoria (confusion, hallucinations) and stimulation when they receive these types of medications without other sedatives.
Do you have a local animal emergency room near you? They may be able to offer other medications that would be more appropriate for kitties.
What other symptoms is she having that make you feel she is suffering? Your question was cut off above.
Can you encourage her to lay in her bed comfortably? She may also be cold, so you can try offering heat support such as a warm water bottle or warmed rice filled sock. I don't recommend heating pads as they can cause burns.
Best regards, ***** ***** this answer helps you.
Feel free to contact me if you have any more questions.
Kansas State University,
College of Veterinary Medicine Class of 2001