light periods with no pms symptoms

Hey guys, the last two months I have had light periods that have not came on time, I don’t cramp or have ANY pms symptoms. it is the same flow the whole time and then disappears as fast as it came, Does anyone have any leads to what it may be caused by?

i’m usually a very on time person, and i cramp pretty heavy 3 days before and 2 days during my period. so these last two months i’ve been a little conceded due to the changes i’ve experienced