Vaginal infection & bleeding

Am 3 months pregnant and got vaginal bleeding by 3a.m. went to KK and took scan of baby. Baby Is safe. They took sample of the vaginal bleeding and gave the report that it is because of infection & gave tablet for 7 days. But still got spotting. They call it as " threatened miscarriage". Do anyone experienced the same and gave normal delivery? I am on my 12th week now. Can anyone explain plz. I am scared #1stimemom #firstbaby #advicepls #vaginalbleeding #vaginalinfection #spotting