The counselors at school are a good place to start. If they can't help, they can refer you to someone who can. Your MD is another good resource.

Please don't let money stop you from getting help. A lot of towns, cities, and counties have a public health department that will see you on a sliding fee or no fee basis. You can find them in the phone book under the name of the county (city/town/etc), or google them on the internet.