Postpartum depression

I'm almost 3 months postpartum an postpartum depression didn't really hit me till a couple days ago I thought postpartum depression was only supposed to last for 6 weeks. If anyone has any tips on how to help myself that would be great I try long hot showers when the baby sleeps or try to read books when she naps or I sleep when the baby sleeps. My apatite has went down alot since I have had her. Cause I keep myself busy an focus on taking care of my daughter cause to me as long as she is healthy an taken care of that is all that Matters. It seems that I have let myself go though I feel really down an anxiety, anxious,overwhelmed,nervous as if I'm a bad mom feel like I don't do anything right anytime would be great.