Round Shakey Head

She was like this last week for 48 hours, so we took her to vet and she gave her an injection of antibiotic and painkiller. She made a full recovery the following day and was back to her normal cheeky self. Then yesterday we found her to be the same way as she was last week, but this time slightly worse. Wouldn't lie in bed and was trying to drag herself round cage. She would only lie on sawdust. We tried to hand feed her but didn't seem to be able to grasp the food and got even more shakey when we approached her. Her head was bobbing up and down. We didn't think she'd last the night, but this morning she seemed a little bit brighter. She is now showing signs of recovery again although still abit cold and quiet. She is able to eat and not as shakey. Not sure weather to take her back to vet. What do you think it could be?