My kid 14 girl hasn't had a bm 4 7 days and she's vomiting stomach pain gave her laxative not working?

Is she constipated? A teenage girl can tell a parent if she has had a hard time pooping. If yes, then she has been constipated, and does need a "clean out". If she has been pooping soft or loose poops, every 1/2 to 2 days, without problems, then she is unlikely to be holding on to a big amount of poop (meaning little will come out with laxatives). The dr. Can decide if an enema is needed (they are over-the-counter).
She is constipated. It is unusual to go 3 days or more without a bowel movement (bm). Vomit and stomachache without fever makes constipation the most likely reason. Think of the GI tract as a river. For normal function , flow must be steady. Your child needs an enema to get the dam opened to start with. After this, enough laxative must be used to keep things flowing loosely for weeks. Try milk of magnesia (magnesium hydroxide) daily.