Hi ladies, so at work today I had someone give me 2 capsules (400mg in total) for a pounding headache I was having. I was under the impression that It was Tylenol since thats what i asked for & a coworker spoke up and told me she had some. Honestly ik its my mistake for not looking at what I was taking but it ended up being advil, now hours later I still have a stomach ache that wont go away.. also, I am having black stool (TMI) accompanied by this. Should I be worried, I am 10weeks along.