I am having severe tooth pain. i had a cavity filled at the end of february but this pain just started about 5 days ago. now its in my ear and jaw.

Call your dentist: If it was a deep restoration, you may need root canal therapy.

Pain: May or (probably) may not be related...may be coincidental. Please return to your Dentist for a reevaluation, differential diagnosis, and treatment, including relief from pain.

See a dentist ASAP: Those symptoms would be consistent with a tooth nerve going bad. This is when the nerve inside the tooth is dying and it will give you pain in the tooth and that radiates to various places on your face/head. The tooth will need a root canal if this diagnosis is correct or an extraction.

Go back to dentist: Pain is your body's way of telling you something is wrong. It could be a crack in your filling or your tooth. It could be a new cavity in a neighboring tooth. Your dentist should be able to figure it out and treat the problem. In the mean time rinse with water and avoid sweet sticky foods. Please don't wait until it gets worse as this could cause the loss of your tooth.