I miscarried one twin at 7 weeks and her sister survived.
My grandmother inlaw was pregnant with my mother inlaw and only lost one, she didn't know she was still pregnant until she was about 4 months along and started showing! Lol. Yep its possible and I hope you get the answer you are wishing for(weather it be yes you are or no you aren't) Good luck :)
I had a friend who had a miscarriage and was still pregnant. Apparently it would have been twins and she only lost one. I didn't know that was possible!