When does it stop being "baby blues"?

I've had a long history of depression/anxiety since I was 12 (I'm now 21).  I still feel overwhelmed and I feel like I need to constantly be checking on DS.  I am so scared he will stop breathing and I won't be there to help him start breathing again.  I sleep horribly at night because of this too.  During the day I try to take naps when he does but it just doesn't work.  I feel like I need to do stuff because laundry, dishes need done. 

I want to cry most of the time, the littlest thing makes me swell up with tears.  I love my son so much and that makes me want to cry.  I have no urge to hurt him but I do get frustrated with him. I mean he's 5 weeks old and can't help anything.  But he constantly wants to be held and when you put him down most the time he cries and I get frustrated because I can't get anything done.  

 My boyfriend is back at work so I am alone most the evening by myself.  We also live with my mom and I feel bad giving him to other people.  I feel like a bad mom when I need to breath a minute.  My mom is dealing with her own stuff right now so it makes me feel bad if I have her watch him for a little bit.  

Most days I feel like I'm just going through the motions.  I feel so overwhelmed and am so scared something will happen to DS and I don't know how to make the anxiety go away.  I'm not happy like I feel like I should be.  You see all these people so happy to have their kids and I don't feel that overwhelming happiness I thought I would.  

I don't feel comfortable talking to my OB about this so I thought about going to my family doctor to talk to them.  But I'm not sure if this is just baby blues still and it will go away or if I do need help... 

Sorry this is so long, I didn't expect this to be a rant...