B.B.
I think you're right on target to be concerned. With our oldest, it was usually an ear infection too. Back in February, she had a fever spike each night for 3 nights, she was eating and sleeping mostly okay; so we took her in and it was strep throat.
Keep an eye on it. Our usual target is 3 days. If in 3 days it isn't better or if her symptoms get worse, then consider taking her in again.
Good luck!