It keeps ringing my head... MEANING -- keeps repeating in my mind... CONNOTATION -- English has a million ways to say the same thing. So, it can be useful to know the meaning, AND the connotation, which gives you a hint about WHY the speaker chose a particular phrase over the million OTHER ways they could say it. I think the connotation of "ringing" is that the remembering is ANNOYING. That is, in choosing this expression, the speaker is saying that it repeated in her mind, but that she wasn't happy about it, it was annoying... When I think of something ringing in my head, it's like I can't get it to stop...like a phone that keeps ringing...and ringing...and ringing. Another good question to ask is: "What does the speaker's choice of this particular expression (over all the other possibilities) tell us about her attitude towards what she was saying?" The MEANING is the same, but the speaker's attitude to the thing in the mind is the difference -- and that is subjective -- depends on the voice, tone, facial expression of the speaker as much as the words. You asked "What does it mean?" My answer is that the meaning of the WORDS is maybe 20% -- the real information / communication is probably in the context (if you read it) or in the voice, intonation and expression (if you heard it). The importance of phonology to meaning (speaker's intent) in spoken English is underestimated sometimes... Hope this long answer was more useful.

I think it is a typo. It should be: It kept ringing through her head.

If I keep ringing through someone's head, it means that they are constantly remembering me or thinking about me.