Greasy hair

Riz
Up until a week ago my hair has been soft and shiny and looked freakin amazing. All of a sudden it got really really oily. At first i thought it was the new conditioner i got. Then i thought maybe my bf or son was using my brush getting all their nasty hair products in it. So i bought new shampoo, conditioner, and combs yesterday. I washed and dried my hair earlier and it looks like i haven't washed it in days. Is anyone else experiencing this problem? If so, what are you doing to fix it? What can you recommend to help get my hair back to normal?