Second period lasting two weeks

[Icyblue]

My 14 yr old dd is on her second period. It is very light but lasting two weeks got me worried. She is fine in herself, no cramping or clots. I know first periods can be irregular but is this normal lasting so long?

It's 2.5 weeks since her second period started. It's only spotting but is this normal? I can't remember what my first periods were like so not sure should I take her to the doctors or not? Thanks.