Please tell me I'm not alone.
I know what I'm going through right now is the baby blues. I just had DD2 on Saturday so its only been four days. But I can't help but feel this incredible sadness. I don't remember actually feeling sad with DD1, just overly emotional and I would cry for no reason.
These past few days though, I have felt a terrible sadness, like someone died kind of sadness. And when I think about why I would feel this way, I just keep thinking "how could I do this to DD2?" Although she is adjusting better than we could have hoped for so far. I just keep thinking that it'll never be just us anymore, that she won't have the one on one time like we did before. I know that I will make time for just her and I, but I'm already missing it just being us.
I love DD2 just as much as DD1, and I don't feel any resentment toward her or anything, just guilty for taking away DD1's only child status. I keep wondering how on earth I will ever give her the same kind of "mommy and me" time that I did before.
The weather has been gloomy here the past few days too, which seems to only make me feel worse. I'll be fine for a while, then feel the terrible sadness come over me again. It seems to get worse at night. I haven't felt this depressed since my cousin died and I hate it. I am not normally this way. I feel so terrible for thinking this way, because I know that I'll work out a way to give each DD their own special time. I just can't help but feel so sad about losing that special time with DD1 and all the changes that DD2 is bringing.
I feel so lucky to have two little princesses now. I just hate feeling so depressed about the changes that are happening and I don't want the relationship that I have with DD1 to change, which I am terrified of happening.
Why do I feel this way? Why can't I feel like myself again? 
Re: Moms of 2+
You are certainly not alone. I felt that kind of sad with LO#1 and not any with LO#2. I got sadder at night and felt extremely cold when which made it worse.
I was sad until I went back to work. Three months later. When LO#1 cried, I physically hurt. I didn't think I had pp depression though. Things were changing a lot of us. Moved to a new city, jobless, new baby, etc. so there several other things going on.
I actually feel reverse from you if anything about not having enough alone time with LO#1. I was so concerned I wasn't going to have enough us time, and give him all my attention. But now that the baby is here, I feel sad for my DD. She sometimes has to CIO because I need to tend to my oldest. Potty training or getting something he needs. I don't cuddle her as much because of the things I need to do for everyone else. I feel horrible and she's going to daycare next week at only 6 weeks.
You will get through it. It will pass. Talk to your husband about how you feel. Talking about it always helped me, even if was temporary.
Although I'm stressed out about doing everything for everyone and giving everyone everything of me, I know that this stage, this needy stage is temporary. And when my oldest no longer wants to give his mommy kisses or hugs, and my little one can sleep through the night without being soothed is when I'm going to wish this time lasted a little longer.
They grow up faster than we know it. Enjoy it.
If you're still sad at your 6-week checkup, definitely talk to you doctor about it. Maybe they can give you something for it too. Good luck and congratulations.
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