3 Days Late. . .

So my period is 3 days late. I've been losing weight which had helped regulate my cycle and it's been regular for like 6 months(I'm on the mini-pill). Took a pregnancy test last night and it was negative-kinda knew it would be. But was wondering if the intense stress from work this past month could cause issues with my cycle? Not sure what to do and I'm concerned if I dont have a period this will cause issues when we start ttc in a few months