dal- just wanted to add my piece on small age gaps...
my 2 have only 15.5mths between them, and i will admit it hit me hard having 2 so close together, however, i do think that was becasue DS had been such a 'good baby' we expected another the same and DD was very clingy and demanding. DS was easily entertained watching me clean etc from a small age, and i wanted DD to be the same so i could still do housework and spend time with DS alone too as he was still so young (with DD watching from playmat etc). But she was very clingy, didn't like being put down etc, so it hit me hard.
when dd was 9wks old i was diagnosed with PND and given AD's. I took them for around 2 weeks and didn't feel any better, one day i forgot to take them all together and the next day too and realised i felt normal, better on my own...
I think the hard time was just adjusting to having 2 babies almost... but within 3mths i was in a good routine with both DC's, and was fine. And now its well worth the hard work!!