bless you
how scary
am amazed you were not told to lay off sex until second trimester
subchronic or subchorionic?
chorion is one of the membranes, the other being the amnion, they are the bag that holds the amniotic fluid, that your baby is , so i presume sub chorionic, if that is what it is , is something to do with that,...
anyhoo, best thing to do, IMHO, is take it easy , call the midwife or obs first thing and find out more, and get this explained to you properly, whihc should have been done
a lot of the time, there is no visible rhyme or reason for bleeding, it settles, and all is well x