You must understand that a tampon cannot go up through the uterus
and be lost in the abdomen, as people sometimes think. The vagina is like a blind pouch . The cervix
is at the deep end. It only has a tiny opening for blood and semen.It is hard and not easily forced open. Tampons have not been shown to cause other damage to the vagina or cervix.
Infections are the only real concern which can result in odor, discharge, pelvic pain
, and fever
So there is nothing to worry much and don't freak out yourself.
You can try to retrieve it yourself.
Wash your hands thoroughly and then insert two fingers inside and try to trap the tampon between your two fingers but if you can't take it out,you can consult your doctor who can do this very easily.