Feb 23 TKR April 2024 broke Femur bone and now this . . . .

I have a nightmare of a week. Memorial day my other knee (left) totally unexpectedly gave out on me and I fell on my right knee then on Wednesday I was using my walker and my right knee collapsed and I fell right on my replacement. I got ex-rays the next day; they showed that two screws have come loose from my femur surgery but the PA said that happens appeared to be not too concerned. I see the surgeon for my femur today but I hold out little hope that they can tell me why my knees keep buckling. Has anyone else experience these difficulties???