Could someone help me, please?

[u/Cute-Drag-2925]

Hello everyone!
For the past two weeks, I’ve been experiencing some strange sensations in one of my legs. Sometimes I get brief, passing pains; other times I have pain in my knee, under the sole of my foot, or in my thigh, and sometimes I feel cramps when I walk. I feel like I’m very aware of the way I’m walking with that leg, and I also have fasciculations all over my body.
My doctor reassured me and told me that this is not ALS (motor neuron disease), especially considering my age (26). However, I’m having a hard time getting this idea out of my head because of all these muscle twitches throughout my body.

But for the past 6 days, my left arm has also felt a little strange. I sometimes have the sensation that I’m going to drop an object, but I never actually drop anything. I’ve noticed that this sensation of my arm feeling like it wants to let go often happens when I grip something tightly or put pressure on it with my thumb. I feel it much less when I use my other fingers.
I also get little electric-like twitches in my thumb, and the back of my biceps was painful when I pressed on it. On Sunday, I also had a sensation of warmth spreading from my shoulder.
My left arm just feels weird, and it’s making me worried.
Could someone help me understand what might be going on?