I have a half chipped tooth. my dentist told me to use braces but i couldn't afford it. i get a lot of headaches sometimes. i've had it since i was 12?

Bad bite / TMJ?: A chipped tooth can be a result of decay, biting into something hard (hard candy/ chewing ice) night grinding or a by product of a poor bite. Your headaches can be bite related as well. If you have been suffering lots if headaches since you were twelve and your dentist suggested orthodontics (but money is an issue) find a dental school or ortho graduate program that will do it at a reduced fee.

Headaches: Headaches, damage to teeth, excessive wear, joint problems, muscle imbalance, can all be caused by, or contributed to, a malocclusion. Your dentist must think there's enough wrong with your "bite" that realignment is required. Talk to an orthodontic specialist. Initial examination often free or low cost. Orthodontists have many creative payment plans.

Different issues: My guess would be that you have three separate issues although it is possible they are related. The chipped tooth can be fixed with composite bonding, a laminate or crown. Crooked teeth can be fixed with orthodontics. The headache may not be related to either. Speak to you physician regarding the headaches. At least get the chipped tooth fixed. Ortho can be done later in life if finances improve.