Dry Shampooo??????I may need the oposite?

I kinda need the oposite. I shower once a week (wash my hair) i bathe every day though. adn like i shower once but that day and the enxt i hate my hair , cuz its so dry , i wnat that natural oils in there but its not. and then after its fine, but my hair in like evening after i come from school , my hair's all good adn together. but when i wake up and comb my hair i hate it, cuz its all like not frizzy (i have natural striaght hair) but its just hard to do anything. like if i wanted to do half up half down do, it would be so hard. Anyone know whats wrong with my hair and what shampoo type i should get-