Thighs feel weak, but walk & run. worried about gbs. i have mild tingling in hands & feet that come & go. what's the outlook if i were to have it?

Unclear : Guillain-Barré Syndrome (or GBS) is a rapidly progressing disorder where an attack on the nerves by the body's immune system causes significant rapidly assending numbness and weakness (typically starting in feet and/or hands and then progressing upwards). If your numbness issues has been going on for a while then it is less likely GBS. However only a neurologist will be able to tell for sure.