Late Period - Strange Cycle

I need some advice/help/insight. I was 7 days late on my period (my period has been every 29 days since I was 10 so it’s pretty regular - and this is odd for me)- I’ve had 3 negative pregnancy tests - and today I got my period but it’s not normal. It looks like it’s the end of a cycle (like brown blood and not really a full normal period). I should add I have been trying to get pregnant for the last 3 months or so and this is the first time since my miscarriage two years ago that we’ve been trying ... so I don’t want to get my hopes up. And I will be going to a doctor as soon as I can get an appointment . But, in the meantime, I just wanted to see if anyone on here has any idea or experience like this. Thank you!