Hello, and welcome.
I'm sorry your cat is experiencing this problem with her ears. Is she also scratching at her ears, in addition to shaking her head? Did you give her treatment for ear mites from the vet or from a pet supply store? I ask, because, technically, the medication from the vet is more effective. Symptoms of ear mites, include debris that resemble coffee grounds--blackish/brownish debris/tiny particles.
If your cat doesn't have this in her ears, she may have an ear infection or another problem deeper in her ear that you can't see, but the vet could see with a special instrument. The two lumps you feel behind her ears might belong there or if you've never felt them before, they might be swellings from her head shaking, an ear infection or swollen lymph glands.
If would be best if you could get her seen in person by a vet, but I understand how difficult it is for you to get her there. You can have a mobile/housecall vet come to YOU, if you have any in your area. This will be much less stressful for you and your kitty. Check out this site and plug in your zipcode, to find one near you:
I hope you are able to have your kitty seen and all will be well! Please let me know how she's coming along. Thank you!
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