Hi Mariposa,
If I can toss in my two cents worth...
I would
strongly suggest that you take a few days off--read a book, look at the sights from a stable position, like a cafe chair. Don't fret; the Camino is still going to be there several days later. This is the most essential thing you can do right now. (It's called relative or active rest. The rule of thumb is - don't do anything that reproduces your pain for the initial two or three days. After that, you need to get it moving or other problems will develop.)
As Mike said above, RICE is now not advised for injuries--but more to the point, for injured tendons and ligaments, such as the patella tendon . If you want to try it, try it but not for too long: 10 -15 minutes at a time; your call.
There are two trains of thought in the treatment world: RICE (rest, ice, compression, elevation) and MEAT (movement, exercise, analgesics, treatments). RICE seems to be better for acute muscular injuries whereas MEAT seems to be better management for tendon and ligament injuries, such as patellar tendinitis. I've suggested a little bit of A and a little bit of B for you. If you can get in to see a massage therapist--or a physio (who will apply either RICE or MEAT practices on your knee and leg)--she or he will be able to assist you with this in person.
The knee strap is great but I would wear that after your knee injury has calmed down. You want a compression bandage or elastic support right now. Don't wear it 24 hours a day; wear it when you are moving around. After the inflammation around the knee has retreated, you might want to wear it while walking for a number of days, as a support. Don't get one that is too small or tight; you want support, not constriction!
The other thing you want to do is to stretch. The quadriceps muscles that attach to the patella are probably overworked and not strong enough. A tight muscle is different from a strong one: a tight muscle is overused and weak, which offers no help in the form of protection or mobility, in this case to the knee joint. One specific muscle in the quadriceps group, the vastus medialis--the muscle on the inside of the thigh--is usually the weak culprit, especially in women. If it is weak, as it usually is in (a lot of) women, it will pull the patella--the kneecap--out of alignment and can set the joint up for a tracking problem and then, subsequently, with runner's knee, aka, patella tendinitis. You need to stretch your quad muscles (and toss in the hamstrings and calf muscles--front
and back) then start to strengthen the quads, especially the vastus medialis on the inside of your leg. Legs, plural. Both legs!
If you can find a massage therapist in Pamplona who has an available appointment, I would also highly suggest seeing him or her. It will help speed up the healing process. There are several there; I'll send you a message with some names and contact info.
Sorry for the long long and clinical note; I am a Registered Massage Therapist in Canada with 21 years of experience; 23 years if you include my training; 8000 years if you include my post-graduate education!
As you are not my client, my information is purely for that--information. As a therapist, I also can't suggest medications as that is out of my scope of practice. But as a pilgrim, if it was me in your shoes, I would make my way to a farmacia for some (natural) analgesics, that contain
proteolytic enzymes, to help with recovery and pain relief. These are more readily available, apparently, in Europe than in N. America. If it was me, I would also
avoid anti-inflammatories.
Get a good book, a cuppa tea, calm your fidgety desire to walk now and rest. In a few days, get into Pamplona and see a massage therapist. You should be good to go after that (but take it easy! don't over do it; you want to enjoy the Camino and not worry about injuries!)
All my best from sunny and warming up (9°C right now!) PEI, Canada!