Leg weakess (reposted for additional details)

So a bit of information about me: I’m 14, male and a huge worry-wart and hypochondriac. 

I’ve noticed these past couple weeks that my legs, my left leg mostly, has felt weak. I don’t work out regularly and I eat a pretty normal diet. Sometimes my leg will just randomly give out, maybe once or rarely twice a day. And if I do some jumping jacks or something they tire very easily and just have an overall weakness. I rarely drink caffiene also. I have generalized fatigue also, even when get 9+ hours of sleep. I have had some symptoms that have passed like muscle jerks/twitching, derealization and others. I also just went through a growth spurt. Could I have some sort ALS or neurological disorder? 

Everything you describe could be put down to anxiety symptoms. But I'm not a doctor so get checked out if you need to!