sleeping a lot, growth spurt?

The past couple week my 3.5mo has been going through a sleep regression, only taking a few 30 minute naps through out the day and waking 2-3 more times than usual at night, also she has been super fussy and fidgety on the boob! Well as of yesterday she's been sleeping like a new born, waking up for some food and maybe a little bit of play time .. could it be a growth spurt