I think depends on colour of spotting, whether it is staining your underwear or you only see it when you wiped. May be more alarming if it is bright red blood.
My spotting happened on and off for 2-3 days, was light brown when wiping. When i went to search it was said that it may be common during week 4-8 since shedding old cells or some form of implantation bleeding. Mine stopped after that and things were ok during my 6 weeks gynae appt.
But of course, do speak to your gynae, medical advice is always better.