Hey Mike, I'm no expert tho i've ben diagnosd with Benign faciulations.. Same thing happended to me with my thumb, chances are the more u think about it theore it will twitch or seem to.. Try relaxing and if your really worried in the next couple weeks then make an appointment for doctor. No weakness then there should be no worries as apparently ALS is only present where there is weakness.
Try taking bath, anythign to relax and keep your mind off it!
I am also no expert but are you overdoing your basketball? Each person's body is made up differently. It is possible that your system is reacting to strainuous physical activity that maybe your body is not built for.
How important is basketball for you?