My Daughter Had Been On Depo Provera For A Year

My daughter had been on depo provera for a year she has gone off of it over a month ago. She had a priod starting march 31 lasting 4-5 days then after her period was done for a week she had 3 days of brown discharge. She has been secually active and she informed me they didnt use protection!! Could she be pregnant? Or is the brown discharge just from hormonal imbalance due to her going off the depo provera?