Persistent Post-Period Bleeding: Causes & Concerns

Question
my girlfriend had her period about four weeks ago and after it stopped like normal about 4 days later she started bleeding again on and off almost every day for the past 3 weeks straight. She has also had normal period symptoms such a cramps and mood swings etc. but not consistently. The past week it has gotten worse with her moods like being really depressed easily, and more mood swings. She hasn't gone to see a doctor and i have become worried for her not knowing what it could be. Do you have any answers that could help?
Also she is taking the birth control pill yaz (im not sure if it's yaz or yasmin)

Answer
Assuming she's been on the same pill for sometime, then something about your girlfriend must have changed, since the pill doesn't change.  The most likely cause of her mood changes and bleeding is stress.  Don't ask me how stress can cause all the changes that she's having, but it can.  It might help her to go off the yaz or yasmin, or switch to a different pill, since what has changed in her body may be how she's reacting to that pill.  However, if she does have much stress, a better plan would be to reduce the stress and work on dealing with it (exercise, rest, diet, relaxation, etc.)  If the bleeding doesn't resolve she should see her doctor.  Best wishes to you both.