Bleeding during pregnancy and placental abruption

I have recently found out i have a bicorneate uterus. I am 12 weeks pregnant. On dec 25 i had brown spotting. 3 days later i went in for a follow up visit with no bleeding in the days between, on that day i visited the doctor they discovered i had a slightly open cervix and dark red blood. the rest of that day i bleed bright red. by night time it had slowed down to a tiny bit of bleeding and changed from breight red to dark red blood. they told me the pregnancy is viable, and it is possible i have a placentia abruption. i have had no cramping at all, no fever, and i feel fine. however my belly is a bit tender and i feel like i a
have been having braxton hicks. is this normal? or is it like i am suspecting which is i am on the verge of a miscarriage?