painn killers

In the past my doctors have tried me on morphien, they give me a does that my dad learned should have put me out, but it barely di a thing. They also tried Vicodin 5/500mg, after about 1 hour my headache went to what I call a # 3 and I got really talkitive. My family says kinda drunk, happy, but it only last one 1/ hour. Sad thing is my headache is coming bach.  This medication is supposed to last 6 hours.   They ar trying me on Meloxicam 7.5mg    My question is it possible any of my other medications are making it more difficult for these pain killers to work?