Horrible headache and fatigue after Morphine?

I went into the ER Friday night because of abdominal pain.. They gave me a shot of Morphine before I left.. I got home at 3am and went right to bed.. When I woke up I had a headache that tylenol barely took away.. Light hurt my eyes and I was horribly tired and groggy.. I slept all day.. Today I still feel very tired and exhausted.. My head slightly hurts.. I have no energy and all I want to do is sleep... Is it possible that this is because of that morphine shot? It actually kind of scares me..