I'm also very concerned that my knees have been buckling lately, mostly when i'm tired and kind of dragging (like shlepping through store when tired, or on waking before coffee). Should I tell my neuro? Had an exam and he said he thought I was healthy (didn't take all my symtoms seriously), but to come back if I had weakness. Don't know if i've always had weak knees or am just noticing it now. It happens once or twice a day now, up from every few days a week ago.
I've had all you describe with your legs too.