Driving myself crazy

I feel like I'm going to go insane with worry during this pregnancy.  I am just driving myself crazy with the possibility that things could go wrong.  Anyone else dealing with this kind of anxiety?  I know it's somewhat par for the course for a PgAL mom, but I feel like I'm taking it to an extreme.  The thing is, things haven't been perfect.  I'm almost 21 weeks but I've had issues, primarily bad blood work that gave me a very high down syndrome risk.  The baby does not have down, but now I'm worried about other issues that might have caused this blood work, especially since a midwife mentioned placental issues.  I'm not showing and I can't feel the baby and while I know this is still normal at this point, combined with the other issues, it's just too much.