I think my cat might have worms?

shes been throwing up a bit lately and poops ALOT and omg does it stink >.< this morning i was cleaning the litterbox and i seen something long flat stringy green hanging out of her poop, could this be a worm? if so what kind could it be? also she haz 3 kittens that are 6 weeks old that still suckle off her so should i give them medicine? and i have 2 dogs that lick and bite and play with her, do they need medicine? one last thing! :P my cats scratch me alot so i should probably take medicine too right? that is if she has worms.