My lower back hurts when i sit down for at least 10min or longer and is painful to sit long. my dad thinks its from cheer, do u think i pinched a nerv?

See below: Depending on where the pain is, it's quality, duration and intensity, whether it radiates anywhere and what relieves or exacerbates it can determine the cause. Without more info, I do not want to speculate, but i would see your doc for an evaluation.

Not enough info: Thre is simply not enough information to try to determine the cause of your pain.