VLM 3 weeks to go....

I have managed to do my knee in on my last long run last weds. Felt like a sharp stabbing pain in my front knee cap and my knee clicks and hurts whenever I bend it.

I have managed to get a physio appt for weds 11th April but wondering whether there will be anything they can do at that short notice 11 days before race day?

Any idea what this injury is and is there anything I can do to speed recovery?

Thanks
Sarah