Spotting when menstruation is expected can actually be suggestive of implantation bleeding which occurs when the fertilized ovum implants
itself into the uterine endometrium.Missed period is an earliest sign of pregnancy. Sore
breasts, nausea, increased urine frequency are few other symptoms suggestive of early pregnancy. Take up pregnancy test if you have missed your periods. If pregnancy test is negative other possible causes could be hormonal imbalances, ovulation dysfunction etc.