Growth spurt

so, why the hell did noone mention growth spurts?!
we have just been through the second spurt so knew what to expect, but the first was a nightmare because we didn't know what was happening.
so what was..?
Seems every 10 - 12 days a newborn has a burst of growth. If you are breastfeeding, the first spurt results in a very hungry and upset baby who will take all the milk you have and still want more. Clearly at that point the crying gets worse and, after you have run through the possible cause again, you will realise that (s)he is still hungry.
This was the first time during the whole pregnancy and birth that I saw my wife show fear. She could not feed our baby. We had been told that the milk would be there, as much as was needed, but now it had run out. What were we doing wrong and how do we feed our increasingly unhappy baby..?
I nipped out for some formula and made some calls for advice. My questions were what is happening? and how much formula without ruining the chance of future breastfeeding?
Expert advice (amazing midwife homebirth team) reassured us that this was completely normal, and enough milk would flow tomorrow. All we had to do was wait and endure the tears, which would be more about communication than actual acute hunger.

So, all good in the end. As soon as we had this information the fear evaporated. But the fear could have been completely avoided if we had known this was coming. We did a good deal of preparation, but missed this. If it happens to you, take heart. It's expected, milk flow was better second time. ...and it will happen again, and again, and again, so you can get used to it ;~)