Will oxycodone and hydrocodone ingestion show up the same in a drug screen for PM? Metabolites, etc?

it could. I would suggest that you take the hydrocodone pill bottle in with you to show that those pills were left over from an old script you had. That way you can show that those pills were yours all along and you did not go out in order to get them from someeone else.

Hydrocodone is a strong painkiller that is often prescribed to relieve severe pain, such as back pain. However, it is important to keep in mind that self-treatment and using hydrocodone without consulting a doctor can have negative consequences.
If you run out of medication and experience breakthrough pain, it is best to contact your doctor or pharmacist. They can review your situation, provide advice, and possibly provide a temporary solution to relieve your pain.
Self-medicating or using drugs without advice can be dangerous, and it can affect the results of urine tests. It is also important to avoid taking more than the prescribed dose, as this can lead to serious health problems.
It is always better to get advice from a health care professional who can take into account your individual circumstances and provide safe advice.