Is this growth spurt?

My 3 weeks old newborn is on 60ml per feed and since couple days ago he can drink up to 90ml on certain feeding sessions. Today I latched him up to 1hr and it seems that he is still very hungry (being crying and fussing a lot) so I gave him another 60ml of FM. Is this growth spurt? Has your baby gone through growth spurt and how was your experience like?