I Am A 62 Year Old Male With Left Knee

I am a 62 year old male with left knee pain. I had knee pain about 20 years ago & after x ray didn't show injury they did an MRI which they diagnosed arthristis on the knee. The Dr. gave me a knee brace, Meloxicam 15mg once a day & and told me it would heal. It did & when it got cold I would put the brace back on. In the years when the pain came back I was given physical therapy, changed to Diclofenac 75 mg then after a few months when it flared up changed to Sulindac 200. About 2 years ago my primary Dr.sent me to the Orthopedic Dr.who said fluid had built up, drained the knee & injected cortizone. In 24 hours it was much better & would flare up periodically. Dec.2014 the pain was on the inner knee not the middle of the knee. I went to my primary care physician who thought I just had strectched the medial collateral ligaments on the inner knee.
I was taking the Sulindac & asked to change me back to Meloxicam & did the therapy. Pain got less then after a mo.or two came on stronger in the middle of the knee so about Mar.2015 I went in again & he did an x ray. There was nothing on the x ray so he said he could refer me to an orthopedic Dr. who I had seen in the past. After debating it with my wife for a mo.or two I finally decided to see the Orthopedic Dr. who is a specialist in the knee. He said the knee was swollen & could tell something loose in the knee. He suggested an MRI. I refused because previously (few years ago) he drained the knee,injected cortisone & it was fine. He did that on June 4th but commented on draining the knee that there was blood in the fluid he drained & that not a good thing. The only thing that was giving me relief was putting ice bag on it 10 min.on & 10 min.off 4 times a night. Friday I felt about better with less pain when I put weight on it but Sat.the pain was back to where it was before the shot. I was to get back to the Dr.in 30 days but do I really need to wait that long since it doesn't look like the cortisone shot worked like last time & I assume the next step would be an MRI.or what would you recommend? My insurance is with Coventry HMO & I really know what managed care is all about.