Should I start methotrexate?

I’m 77 - have had three major joint operations in this past year; left rotator cuff, left partial hip replacement (not a planned surgery), and left knee replacement. The hip replacement was a breeze, others not. Plus I get injections and ablation for back pain. Knees and shoulders were because of active life (my lupus has been livable with limitations). The back and hip are from falls. However, the pain of recuperation and physical therapy has just seriously ramped up lupus flares that last several days, I feel better just in time for my next physical therapy session! It seems to me my body, my lupus, has changed throughout all this. Because of a mess up of appointment scheduling I’ve had a week off. I had time to feel a little human again, good enough to get a much needed pedicure (I can’t reach my toes without pain) and a haircut. At the pedicure I asked they not do a salt scrub, the last time irritated the arthritis on my big toe. So they gave me the paraffin wax thing, and then a vigorous massage of my calves. She seriously plowed into them!! My toes look great, my back was hurting (I sat too long), but I was glad to get that done. Later that evening my calves felt like they were on fire!! All through the night they burned, until 10:00 the next morning! I guess saying they were over stimulated is an understatement! Is that a lupus thing? It seems almost any, everything brings about a flare. I guess they’re flares - I hurt in my joint areas (even replaced ones), my feet, arms, etc., debilitating fatigue, etc. The pain from physical therapy puts me in a flare until the next appointment. These flares aren’t as long as some I’ve read here, so I wonder is it really a flare?? I don’t know, but it’s been constant misery for this past year. And I can’t carry in the smallest package into my house without collapsing in bed in order “to get over it”. I’ve been watching YouTube videos about Methotrexate, my hair dresser (wonderful person!) is on it for a gastrointestinal thing (not lupus), she said it saved her life. I’ve avoided trying it because as I understand it once you start something other than plaquenil (which I’m on), you permanently damage an already messed up immune system. But at this point in my life - if I can feel better, I’m considering it. Am I too old (77…personally, I’m shocked by my age!) to try methotrexate? Are there any other “old timers” here?