Greasy hair

For months now, my hair is so greasy I feel like I’m a teenager again 😭 I’m 23. I was on the pill for almost 3 years but I stopped in March. I can’t pinpoint when my hair started getting super greasy but even after one wash it’s still gross. I guess I have to change my pillow case more frequently?? Dry shampoo doesn’t help. It’s embarrassing honestly. Anyone else dealt with this??