Hello and thank you for your question.
It is very possible that your knee cap has dislocated or that you have formed fluid behind your knee cap causing you these symptoms. Simple contusion should be going away by now instead of getting worse especially if you have been icing it.
My recommendation would be that you go back to your GP and ask for an x-ray of your knee. If x-ray does not show any abnormalities, you might benefit from having MRI of your knee which looks more at soft tissues such as ligaments, tendons, muscles.
I hope you find this information helpful. Please feel free to follow-up with any other questions you might have.
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Best wishes and good luck,