I have the same problem...only I just don't have my period. No depression, stress. I don't know whats wrong, but I suggest you talk to a doctor, I'm making an appointment soon. Other than that, I suppose it could be stress, which could be linked to depression...so I'm assuming stress/depression could be a Cause for missing your period for so long...but I'm not sure if it's a side effect. Try to relax I guess, eat and sleep well and try to find out if depression is the side effect or cause of your lack of mensturation. :]
Progesterone. It does not really have an anti pregnant effect, but makes your body think you are pregnant.
Aside from pregnancy, there are a lot of different things that could be going on in your life that could be the reason for a nine day MIA of your period. One big factor that happens to everyone is STRESS. This is most likely stress related. Stress can come from almost anything, sleep loss, school, work problems, money matters, relationships, anywhere. You can be stressed and not even know it. Although, it doesn't mean that you shouldn't be cautious about the idea of being pregnant, unless you're not sexually active. If you are, I advise you to get a pregnancy test. In the mean time, RELAX and take it easy, do not get involved with anything that can stress you out.
by your farting
Yes, it can.
the great depression
The Great Depression.