I have a big red spot covering my armpit that looks like its irritated. but it doesnt look like most ringworm spots. what do i do??

Show it to a doctor: A rash in the armpit could be one of several things. I would be most concerned about an abscess or a localized infection (say from shaving)-esp. if it's PAINFUL. If it's more flat and non painful it could be ringworm, a contact allergy (deodorant?), or a more mild infection called folliculitis among other things. If you have any underlying medical problems, that may help the doc to figure it out.