Help with EEG results?

Hi out there! My daughter had an afebrile seizure on 5/07 after she had been sick for a couple of days...but we do know that there was no fever accompanied by the seizure. Her neurologist ordered an EEG and these were the results:
"EEG was abnormal because of the intermittent polymorphic slowing left posterior quadrant and asymmetry of posterior dominant region, less well formed on left hemisphere"

She since has had a normal MRI and we were told everything is fine and to resume normal activities.
Background on my daughter is she has always been kinda one step ahead...early walker early talker, she scored in the Superior range in an IQ test and her only issue was her very high anxiety which she received services for and today is doing great!

I still cannot shake this feeling though...I do not understand the results and I guess they are just haunting me because I do not know what they mean...I've search the web and get mixed messages so if anyone can help me out with this I will greatly appreciate it...Thank you very much in advance for your time. ~~~> Natalie

[Neatalia]

Also wanted to add that the MRI was without contrast. ~~~> Natalie