Help please! is constant mild cramps normal during missed period ?

Probably not.: Cramping is usually caused by uterine contractions but sometimes what feels like cramping of the uterus is really something to do with the bladder or bowel. If it is the uterus that is cramping then lots of things that dont involve having a menses can cause it: early pregnancy, infection of the uterus, a fibroid or polyp. Sometimes for no reason that we can find. Best to check out with a gyn.