Usually not. Even though it's legal, the hotel can still refuse to rent a room to you if you try to rent without parents present. Not just that, but if your parents don't agree to this, it is considered "running away" and they (therefore, you) can be held accountable for your "delinquency."
you have to be of age to check into a motel under your name. I am not sure of your family situation but have you tried talking to them and letting them know you need a little break... maybe they will let you stay with a friend or other family members. good luck and chin up. teen years are not as bad as you think. when u r grown u will look back and see that :)