I live alone and pay all my bills so I file as head of household?

No, you do not file as head of household. Head of household has a special meaning on a tax return. It does not mean that you are the person in charge of the household or the person who pays the bills. Head of household is a filing status for a single person with a child. To file as head of household you must meet all of the following requirements.

1. You are unmarried or considered unmarried on the last day of the year.

2. You paid more than half the cost of keeping up a home for the year.

3. A qualifying person lived with you in the home for more than half the year (except for temporary absences, such as school). However, if the qualifying person is your dependent parent, he or she doesn't have to live with you.

If you are not married and you do not have a qualifying person, such as a child who is your dependent, then you cannot file as head of household. You have to file as single.