I think my cat has an injured tongue?

I have a 5 year old cat that I brought to the vet 2 weeks ago for a spot on her back & ear that looked irritated, crusty & sore. The vet said it looked like a bacterial infection and gave me antibiotics & an ointment. It cleared up rather quickly. Then she developed the sniffles. In the past a vet recommended giving a cat 1 mg of liquid children's benadryl. I did this yesterday & I know that it is normal for the cat to drool because of the flavor but she had a little bit of blood mixed in with the drool. It cleared up & she was acting better. This morning she is acting a bit lethargic and she is eating & drinking but with some hesitation. She is pawing at her water bowl & it's almost like it hurts. She seems to get a better drink from the running faucet. She tried to clean herself & stops. Her tongue was going crazy when she was drooling, is it possible that she bit it & now it is sore?? I can't see anything but it's hard to get a good look since she freaks out when I open her mouth. How long does it take for an injured tongue to heal? I really can't afford another vet visit but will find a way if this sounds serious. Any advice is appreciated. Thank you.