Postpartum Anxiety?

Sara
Has anyone dealt with overwhelming anxiety since giving birth? I'm 4 weeks postpartum and although a lot of days have gotten better, it's still lingering. I've struggled with anxiety in my past but never to this extent and it's been years really since I even noticed it. I worry mostly about my health. I did deliver 3 weeks early due to preeclampsia and my daughter spent a week in the NICU after birth. Now I worry about my blood pressure, my heart, blood clots etc. You name it, I've stressed about it. I don't know why but I'm just so worried that something is wrong with me or will happen to me. I don't know how to shake it.