When mine do this it can mean it's getting too much sun and not enough water. Also not having enough humidity during the winter. You could get a lil humidifier to keep near it, and make sure it isn't too close to cold windows or air vents!

I walked to the grocery store .2 miles away and back while still managing to be able to get out of bed the next morning without too much awful pain. I haven't been able to walk that far in years.

I like doing chair yoga when I'm having severe flare ups! There's some good youtube videos on it, and it's safe for ankles and wrists!