I...I don't even know what to say... I should take her to Doc Church just to be sure everything is normal. She was fine upon leaving Rivet City.
Actually, if I'm not mistaken, this is happening due to this mod outfit. I remember a long long long time ago when wearing this outfit, my characters head turn to the left and upwards and was stuck in that position after wearing this outfit for some time. But it never made my character's head upside down.