What's going on ?

Okay so we have been ttcing for over a year with the loss of our twin boys on 2/13/13 ... I haven't had a period since jan28 ... I have had 6bfn and I have pcos ... Well the past couple of weeks I have been so tried ( this is not normal for me )... my boobs hurt like no tommorow ... My moods swings are terrible !!! Has anyone ever had bfn and still been pregnant ? I am so worried that I might be .. I am having surgery on my shoulder on the 16th I am so worried