Well Oxycodone is a strong opiate. A good dose for a beginner should be around 10-20mg, but you should problem start with 10 to be on the safe side as some people experience nausea with opiates. Like you said, they contain 5mg each, so 2-4 of them to start with. As for the acetaminophen, thats a non-narcotic analgesic. At higher doses it can cause liver damage and be problematic. You want to keep below 4000mg a day of acetaminophen. So you shouldn't take more than 13 of those in a day.