Bleeding after sex

Angel • I am going to be 35. I have a 1 year old after 5 losses and a blocked tube. We just found out we are expecting #2!!
I'm 19 weeks 3 days and everytime my husband and I have sex I bleed. Does anyone else have this happen? My placenta is low and in front and I'm wondering if that's why... I go to the dr next week for my 20 week ultra sound so I'll ask then but I was hoping I'm not alone.  
UPDATE: I had my 20 week scan and my Dr told me to stop having sex the rest of my pregnancy