No period for one month the next month is light but its light red that turn brown for two days now. why is this?

DUB?: You may have DUB dysfunctional uterine bleeding, a common occurrence caused by continuous estrogen stimulation to your uterus. Was your period on schedule or irregular? Did you have a recently positive pregnancy test? Are you taking hormonal contraceptives with recent dose change? You can watch your periods for 3 months since DUB may correct itself. If not, see your clinician. Hope that helps.