Trying to figure out whats wrong w/ my dog....?

My dog(almost 11 mth old dachshund) has been crying and rubbing the side of her mouth on the floor and the furniture all day and it is swollen and her skin is like drooping down. Is this a tooth ache? does anyone know? and if so what can I give her to help. Please let me know, I dont have enough money to go the vet right now to see whats wrong so I need some opinions.