Baby “freaking out” after first two days in daycare

My 16 month old baby just started daycare a week ago. Today was her 3rd full day. She is usually a pretty chill baby girl and the staff at the daycare said she is super participative and easy going.

The thing is the moment she gets into the car for us to go home until she goes to bed she “freaks out” from screaming when she gets into the car (she never really screamed) to switching between super high energy (“telling” us stories of her day) to getting really cranky for no apparent reason.

Is this normal behavior? Maybe it is the amount of stimulation she is being exposed to the first time? Is she just tired? Maybe she is just mimicking what she sees other kids doing?

we will bring this up on her upcoming appointment at the pediatrician but I wanted to hear from this community.

Any suggestions are appreciated.