It disappoints me that we rarely hear about the other side of parenting - it seems like a taboo subject to admit you're not coping or unhappy. Society puts so much pressure on people to procreate - I have always believed parenting is not for everyone - just as not everyone is a suitable candidate for the fire brigade or medicine.
The consequences of doing it and being unhappy are frightening - you can't give it back - I think its the biggest decision of your life.
That's why I didn't do it ... I watched my mother and aunts raise their children and knew at a very early age that I wanted to do something else with my life.
I really feel for people who are unhappy in the parenting role - I fear that may have been me if I had given into the sometimes overwhelming pressure.
I can't imagine how people manage with special needs children and multiple births. I was reading about a lady that has two small sons with autism - her life was a living nightmare - she was desperate for respite care.
Perhaps, you could have a day a week to yourself - ask family and friends to take your child so you can have some "me" time - also, maybe take a part time job - perhaps its just the shock of a totally changed lifestyle. Perhaps time apart will help - also, sleep deprivation can lead to depression or the blues - if you're not getting enough rest maybe you could sort out a timetable with your husband so you both get some sleep or get someone to mind your child for a few hours in the afternoon so you can get some rest. Get some support from the people who love you.
Good luck to you - I hope it all works out for you.