Taken accutane , got weak erections and no morning erection, recently classed with slightly anemic and low ferritin levels?

Look for cause: I am more concerned about your low serum ferritin. If you are not on an iron-poor (vegetarian / junk food) diet, or having enormously heavy periods, we need to find the cause, which is loss of blood into the gut or elsewhere. "slightly anemic" is like "a little bit pregnant" -- in someone who's 18, you deserve to have the real cause found by a diligent physician. Good luck.