So confused..

So first off, I have regular periods. I’ve never been late unless I’ve been pregnant. I was suppose to start today and the only thing I’ve had was light pink spotting. I waited all day for it to show up but the only thing that has showed up is very light pink spotting that’s only there when I wipe and nothing else. Has this happened to anyone else? I’m actually not even cramping. I’m only having some lower back pain but it’s not bad. This has never happened to me before so I’m alittle confused. I always start on time and my periods aren’t heavy but they’re not light. So if anyone could help me, please comment and let me know. Has anyone experienced this? Did this lead to a positive?