Period

So my period is late 3 days now and last month I had a heavy period and I haven’t had sex for a month by I think I could be stressed and I had been cramping and I wiped today at like 5 and I saw red blood so assumed it was my period but now I don’t see anything took a test a couple of weeks before and it was negative so at this point I don’t know what to do. But I see everybody else is late. Is this my period coming ??