Eating sunflower seeds. I think one poked my top left gum behind molar. Is inflamed and swollen. Haven't had tonsils or wisdom teeth removed. Concerns?

Swollen gums. It might resolve on its own or... there may still be something stuck under your gums or... it might be getting infected. See your local dentist to have this evaluated. Rinse with salt water and make sure you continue to brush and floss properly meanwhile.
Rinse vigorously. Try to gently dislodge the seed by rinsing or using a small head toothbrush. If you are unable to get the seed out, it will usually dislodge on its own, or see your dentist for evaluation to prevent further damage.
See a dentist ASAP. A gum abscess, or tooth abscess if not treated it can worsen and result in the destruction of bone tissue.The only way to cure a gum abscess is with dental treatment. See your dentist for consultation.