What are these sensations

I’m pretty sure I have alexithymia because I can’t sense my emotions, I need to attempt to identify them using my body reactions and tensing up. But instead I feel a lot of physical sensations for no reason. When wearing my school bag (14yo) I get chills on my right arm, as well as in other areas randomly even if it’s 34 degrees hot and I’m sweating. I also randomly feel a tingling sensation every now and then, and I can never fully figure out where it comes from. My muscles tense randomly, and my vision goes white for a split second when I stand up which leaves me slightly dazed and confused each time. Even when I’m exerting myself and my lungs are burning my body doesn’t feel much, just a bit of tension even though I know I’ve pushed myself and should be aching all over. No matter how exhausted or tired I am my body feels largely the same. I get pains in my chest for no reason, and occasionally twitch with no triggering stimuli. It’s all really weird and I want to know what’s up with me here (I have more pressing things to worry about rn and I can’t figure it out myself)