Faked pregnancy?

a girl I know split up with her boyfriend but continued sleeping with him, then one day dropped the bombshell that she was pregnant. her ex is a friend of my b/f, but she got quite clingy with me during her "pregnancy". She kept it close to her chest for a few weeks, only telling me, another friend and her ex. Then one day, she announced it to the group. I started getting suspicions, as she tripped herself up a few times (being 16 weeks for a month, knowing the at 10 wks etc.) I confided this to my b/f who agreed fully with me, then the following week a whole lot of drama blew up when it was discovered that she was actually lying. She maintains that she wasn't, and lost the baby, but couldn't tell her ex as she thought he would be devastated. although nobody can prove whether she was or wasn't lying, the whole group has abandoned her save myself and the other friend. My worry is that she was telling the truth, and me questioning it with my b/f has caused the doubt?