11 year old cat not eating after 3 year rabies vaccine

She got her 3 year rabies vaccine last Friday. She was ok for a couple of days but she stopped eating on Monday and Tuesday. We took her to the ER on Wednesday and they gave her anti nausea meds which helped; she ate when she got home. But then when the medicine wore off she stopped eating again. I brought her to the vet today (Friday) and they gave her more anti nausea meds which again caused her to eat a little bit. She’s now hiding and hasn’t eaten any more. Could this be a reaction to the rabies vaccine? Will my little girl ever eat normally again?