knee inflamation

I am writing this messege in english since i am not in Israel. I went for a long trekking journey. A day after I landed I started to suffer from strong pain in my knee, first in the outer side and the it moved to the inner side, center, below the knee cup and theninside the knee. I almost could not bend my leg to 90-140 degrees. Went to a clinic and after x-ray they said I have inflamation and gave me diclofenac potasico 75mg, 2 a day, for 5 days. It helped a little, but 1 day after I finished it became worse again. I took the pills 5 days more. still no advance. I went again to a hospital and they gave me the same but 100mg for 8 days. It became better and then down again. I also rested complitilly for few days with ice. then went to another doctor, another x?ray and he gave me diclofenac potasico 50 mg, with betametasona and cianocobalamina. this doesn´t help as well. He want´s me to do MRI, which is quite expensive. What about voltaren or kortizon injection? In the past I had knee pains, but never had an inflamation. I came here especially to trek and need to recover as fast as posible. do you have any ideas that weren´t done yet? thank you p.s. I can read an answer in hebrew .