Popping sensation in lower abdominal?

Earlier today I went to the bathroom and I noticed I had a dark stool almost black and i'm really scared, I ate some skittles about 2 days ago could this be the reason for my darkened stool? and another thing is when I lift my right leg up to cross it I feel a popping sensation in my lower abdominal but it only happens on my right side do you think I have something wrong with me should I go get checked out? Sorry I'm only 17 and i'm a girl so I get really scared lol but does it sound like a have any intestinal problems? or is it my groin popping? please help :/