Suggest Suitable Medication To Manage Pain

Hi... I have been switched from percocet 10/325 to Opana 10 mg. IR, but I need 15mg, however that only comes in ER. I was told to cut in half the 10 mg IR to make 15 mg. IR. However; I think I need 20mg and do not know if I should take the other half. I am so tired of drugs and trying to find the proper drug to relieve the pain. I need a drug that does not mess with my mind, I have to live as much of a quality of life as possible. Thank you !