You might have a Non vital tooth (A Dead tooth). This can be fixed either by Root Canal or Extraction of said tooth, depending on the extent of damage, which can be found by IOPA (Xray).
Next Steps
1. Get an opinion of a Dentist after XRay
2. Check for your options. (Apart from Veneers you may also Opt for Implants depending on the suggestion of the dentist and your Budget)
3. Make sure to get a Routine checkup done every 6 months atleast
Health Tips
If you get Veneers or Implants. Ask the doctor for durability as the Veneers or Implants may break upon chewing foods such as Meat, Nuts and other hard substances in your diet.
Note : Nothing will be as strong as your Natural Teeth, so if the Doctor suggests that the tooth can be saved and made Aesthetically beautiful without Implants its best you follow that regime.