9 week old was sleeping great now not so much

Ugh our 9 week girl was sleeping great a full month started off with only having one midnight feeding and getting up around 6/7am then it got even better with sleeping from 10pm to 5am but randomly this week she went back to waking up every 2 hours 😩 is this what sleep regression is ? Is this cause a growth spurt is there anything we can do ?