Hey, Boo ...
That doesn't sound at all like ALS ... first of all, you can completely ignore the fact that one leg is slightly different from the other. Our bodies are never identical on each side. You just have probably never looked this hard and compared your legs before, but this is not a symptom of anything.
About the twitching. This does NOT sound like ALS twitching, in my experience. (But I'm talking only about my own experience ... ) ALS twitching is very subtle ... I cannot feel most of the twitching in my left arm and hand, which is where most of my weakness is so far (besides bulbar). And I even have to stare pretty hard to see it.
The rule to remember about ALS is that weakness comes first. If you have a powerful twitching in your leg, but no weakness, then it is not ALS. The way you will detect weakness is if you can't do something normal that you have always been able to do, like pick up a bucket of water, or turn the ignition key.
Also, ALS twitches don't stop or start when you change position.
Please check out the Benign Fasciculation Syndrome forum. BFS twitches are very disturbing, and they are much stronger, generally, than ALS. All "benign" means is that this condition is not going to kill you, only drive you crazy. It doesn't mean BFS twitches aren't real ... they are VERY real.
Talk online with BFS sufferers, and I bet you'll get a lot of reassurance that you're not alone. And you'll also get some tips on how to cope with BFS.
Good luck.