Big freaking problem

Ok ladies my baby has her first tooth! It's out with a second one just underneath the gums. Problem is today she's biting the hell out of me while nursing. It's so hard that I tense up and not move her for fear of her bitting off my nipple. Seriously. She'll let go when I yell in pain. I've been yelling in pain all day and now my husband is giving her a bottle of formula (hasn't had any formula since her first week ☹️)  bc I don't have anything pumped and she's starving. How do I get her to stop biting me?!