Does anorexia cause stunted growth if I'm a teenager?

Yes. Anorexia can cause stunted growth for anyone who hasn't finished growing yet, which usually means all children under 16 years of age. Anorexics don't get enough calories, protein, essential lipids & amino acids, vitamins, minerals, calcium, etc... Therefore, they don't have the necessary building blocks to keep growing at a normal rate (the amount of stunting is less if only mildly anorexic).
Yes. It depends if the person has stopped growing. If a teen still has the potential to grow, by having the long bones not yet sealed; poor or inadequate nutrition from any cause may interfere in growth.