R.K.
It could be an ear infection or teething. Two of my kids and one grandchild had teeth before they were 4 months old.
Make sure she is getting plenty of fluids and has enough wet diapers. You could also see if there is an emergency number for a nurse connected to your ped's office and call for advice. If nothing else call a local ER and ask for advice. If they are not horribly busy they can usually give you advice over the phone.