Knee inflammation, pain , unable to walk

I have pain and swelling in my right knee from last night and i am unable to walk or lift my right leg. It feels like their is some kind of fluid and my muscles got tight.  slight movement increase the  pain. Using a pillow to keep my leg slightly inclined has helped in reducing the pain and applying ice pack too. My ESR rate was 56 and i was on medication. This thing happens to me once every year now. I visited a doctor and he prescribed me some medicine which helped few years back. But as it happened again , i am not sure if i should take the same medication . I believe the problem is something different. Is it a sign of arthritis?. As i am unable to walk or lift my leg so i can't visit a doctor. Any leads here will be really helpful. I am attaching the prescription to know if i can take the same medication this time or not. Thankyou