Working nights, kids and breastfeeding...

Please help
I have been a mfp member before and did great with alot of community support!
Well this time I'm up against a couple of challenges the biggest is working nights. I am working 3x 9hour shifts in a row and then once I'm done I have to look after my children I will usually manage around 3-4 hours sleep through out the following day, most of this after my other half is home from work. I don't know if I should be allowing myself more calories on these days or not, when I'm at work I do get hungry! Obviously if I'm not working I don't eat while sleeping! Any ideas on easy and simple meals/snacks for the day's after work would be great as biscuits etc just isn't a route I want to continue taking.
My second challenge is I am still feeding my daughter, although it's not exclusive probably 3 feeds a day should I be allowing myself extra cals for this?

Thanks for any help
LadyK