Abdominal pain , morphine hiding something

2 days ago i was having the worst lower right ab pain, it was like a knife was going thru me, that last time i had this was about 9 mths ago 2 weeks after my full abdominal hysterectomy, they found a 10 cm mass, the pain has a eased but i also take 60mgs of morphine a day for other thing, can it be making the pain ease up also, i have light headeness not really hungry, not sure about fever no thermometer when i touch my abdominal area on the right it hurts but it hurts more when i let go, back hurts some should i just go to the dr, or should i hold off on the morphine and see what happens with the pain...im a bit confused at what the morphine might be hiding ...thanks for the help