Blood Blister on Placenta

Hi All..my name is Courtney & I am new to "the bump" I am a former knottie. My husband and I have been married for 8 months & we are expecting our 2nd child in January. I just wanted to share a little bit of my issues I have had with this pregnancy and see if anyone has or has had similar symptoms. We are for sure pregnant we have taken several home tests, blood tests, & we even seen the heart beating. However I have been bleeding for about 6 weeks. The doctor says I have a blood blister/pocket on my placenta which is causing the bleeding. Has anyone ever heard of this? Although they seem to reassure me everything is okay I am still a little nervous. Thanks for reading!!