Could be that she is teething and the swelling in her gums has caused more discomfort from the mild cold, the ears and the teeth and the nasal passages are so close together. We had lots of luck with the Hyland teething tablets and motrin.
You should keep an eye on the fever, it was kind of hard to tell from your post, but if she had a cold or was getting over a cold and then started running a fever, that could be a sign of a secondary bacterial infection. Some times kids will run a slight fever when the cold starts, but if it comes on at the end of the cold, then you should probably have that checked out.
Keep in mind too, if she is still running a fever above 99.6 the rule for school (and I would guess most day care) is no fever for 24 hours without medication, for the safety of the other children, just in case she has something contagious!
Take her to the doctor if it makes you feel better, don't worry about seeming like you are over reacting, that is what they are there for. I would take her if it goes on for many more days, especially if you have to stay off work because of the fever. Your day care might let her come with the fever if you have your doctor check her out and says that she does not have anything contagious, but if she is feeling bad, you probably would want to be with her anyway.
M.