I am afraid I have early onset ALS. Left leg and left hand aches and cramps. Finger tapping rate slower in left hand which is my dominant hand.?

Not likely. I doubt ALS but if concerned you should seek consultation with a neurologist.
Comes on differently. What you have doesn't describe the presenting features or EVEN the LEAST COMMON manifestations of ALS. Not sure which blog site you looked at that got you excited but I can think of 100 different other things that are more likely to give your symptoms & none are even dangerous let alone fatal! Get your billions back America! LOL If you'd like to consult 1-1 write me: www.healthtap.com/drsaghafi.