shish, I am in similar situation, ds 2.7, dd 8 weeks.
We are getting into sanity now.
I am basically doing a fairly consistent 8 am to 8 pm routine with both of them. DS always had a 7 to 7 routine which got shifted later as he got older. I have to say 7 to 7 is better for babies but I have to have them on the same times to be able to survive!
The way I cope (if DH not around which he usually is in the mornings) is:
get DS up and dressed, porridge on, around 7.30
get dd up and breastfeed while DS eats
at 9 am DH minds DD while I take DS to nursery (if he didn't, I would have to start her day earlier as she would fall asleeo on the nursery run)
back at 9.30 am.
10-11 DD has a nap in her pram while I jog with her, or a nap in her cot while I conk out
11 am I wake her, feed her, play with her
1-3 more or less she has a sleep and so do I
3 pm I wake and feed her.
5 pm set off with her in sling, having pre prepared DS and my early supper. (I eat with him otherwise get very nazzy). also pop for groceries on way to nursery
5.30 pm back with both kids, she goes in bouncy chair while I serve tea and eat myself,
6 pm breastfeed on couch, while reading a few books with DS or pretending to be on a plane
6.40 or so, into bath with both. put him in first, then her, get her out first, dress her, leave her on changing table while get him out and dress him, make his bedtime milk.
7.20 he has bedtime milk while I bf her, read him a story, put him to bed, then take her into our room, offer a bit more milk, put her down hopefully both asleep by 8, then wake her at 11.30-12 ish for late feed. I also usually have a sleep in the evenings on the couch! as she's up again at 5 am on the dot, as if she's set an alarm!
all I can say is it is very, very hard, and I have it very easy, DH around a lot, nursery very near etc, and you will find your own rhythm, stay strong!