you can also get dry shampoo that has cornstarch in it. This will help absorb some of the oil and keep it presentable if you want to opt for an extra day with out washing. Treseme make a brand you should be able to find at most big box retailers or drug stores.
did you shampoo your hair also? maybe you have naturally oily hair, if so try a shampoo that is for oily hair. I have noticed that for myself I need to change shampoos every other time I wash my hair, because if I use the same shampoo every time I wash my hair, it does the same thing yours does it looks terrible, so I use 2 different shampoos
Well if you're between about 9 to 21 then it could be hormones. Hormonal changes occur during puberty which causes skin/hair to be oily and look dirty. No matter how many times you shower, it may still look that way. But if you're older or younger than that then perhaps it is something else entirely.