Colostrum has a ridiculous number of calories per drop, it's designed to tide them over until your milk comes in, even if that is 3 or 4 days, they are also born with additional fat reserves to tide them over this period. Don't get panicked at this stage that they are starving - it feels like they are but they aren't.
Also the longer the baby is at your breast (or even just lying skin to skin on your boobs) the better your milk will come in. Nature sucks a little but baby fussing (read getting shrieky) at your breast actually encourages your milk supply - so if they are fussing - leave them there don't run for a bottle. It's not a sign that you aren't making enough milk - it's the baby's way of getting your body to make more milk. Every time baby is at the breast, think of it as a letter to your boobs to make more milk.
BF is such a mine field mentally, you have at times to go against your rational instincts and just trust nature. I can see the appeal of FF if you are anxious because you can see the ml of fluid that the baby is taking - with BF you just have to rely on your boob feeling less full (and you dn't even get this in the first week as your boobs feel so engorged) and whether baby is producing wet nappies and whether they are screaming at you!.
The very worst thing you can do in the first few days is try to put baby on a feeding schedule - that will just stuff your milk supply. Babies and boobs haven't heard of 4 hourly or 3 hourly feeds. 4 hourly feeds initially would kill BF as that's just not regular enough to establish a good supply. Basically if you are sitting down, baby should be on your boob! If you are not, go on - sit down, have a cuppa, and put baby on your boob. It's natures way of getting you to slow doooooown and recover from birth. And bear in mind that BF even one month down the line is NOTHING like the intensity of the first fortnight when you are establishing your milk supply. It gets SO easy, but you have to do the hard bit first and after an exhausting labour and the mental upheaval of having a baby it does really test your mental and emotional reserves. I'd recommend getting your partner to read up on BF too as lots of blokes panic when baby is crying and fussing at the breast and are desperate to get formula 'to help' whereas what they need is to 'chill the f*ck out and remember this too shall pass'.