Congratulations.
There is 14 months between our dds. It was fairly hard at the beginning, we moved when dd2 was 6 weeks old to a tiny village, and I don't drive, but it still wasn't half as bad as lots of people predicted/intimated it would be.
I think the most difficult thing was the constant juggling of two babies, dd1 was and still is a very clingy girl, she didn't walk until dd2 was 2 months old and sometimes it felt as though I didn't have enough arms or a wide enough lap.
I had worried about dd2 taking my attention away from dd1, when she was only a baby, but i hadn't taken into account the wonder that has been watching their relationship develop right from day one.
I never had a routine for them, my aim of each day was to get out of the house and see friends, dd2 had most of her naps in the pushchair, I spent a lot of time in coffee shops while they both napped.
I have made my profile public for a bit, so that you can see how close they look in age, they love each other so much, and for the last couple of years (they are 4 and 5) have entertained each other, comforted each other, made each other hoot with laughter (usually by talking about poo) and of course fought a fair bit.
My advice would be, don't worry too much about letting stuff slide, don't worry about making a rod for your own back - whatever gets you through the day smiling (or at least maintaining your sanity!)
By the way, the last photo on my profile, gives you some idea of the chaos and happiness!