Brownish discharge/bleeding pregnant?

So my periods are almost always like clockwork, they're always on time, they always last the same amount of days, they always are about the same flow, etc. This past weekend, I went out of town for the weekend and was very stressed and my period was 3 days late and I figured it was because of that. Started bleeding very very lightly yesterday and I use a cup so I put it in assuming I would start bleeding a lot because that's typically what happens. I had taken 2 pregnancy tests a few days before my period was suppose to start and they were both negative. I woke up this morning and checked my cup and there was still no real period . It was just brownish and very very very light. Like barely anything at all. Could I be pregnant??