I feel like I'm not in control of myself?

I used to be really happy and loud and energetic, so I’ve been told.
But for the past few years I’ve grown quieter and quieter. It feels like it’s not in my control even though I know it is, really; like there’s ropes holding me down or something. And I don’t know why.
When I try to talk my throat starts contricting, when I try to smile my chest hurts.
I don’t feel very much anymore, I’m kinda… I guess you’d call it numb, in a sense?
I really love the people I’m surrounded by in my life, they’re all like family, but it hurts to be around them.
My mind will go blank when I’m put in the spotlight, I have to fight myself for control…
There’s also been moments when I realize I’ve kind of blacked out for a few seconds, because I’ll be in the middle of saying something (which I rarely do, because I feel like I can’t, so people listen hard to my whispers I get out…) and I’ll have no idea what I was saying. It’s scary.
Those people around me have begun to worry, and are trying to reach out to me, but it’s like I’m living in a fog, I can’t reach back to them. I hate being like this, because I’m just in the way, really, I don’t give opinions or say anything or contribute, but everyone lets me stay while I “work out” whatever my problem is. They tell me to talk to someone, it doesn’t have to be them…
They want to see me “happy”. That’s all. They think I’m shy, or have a lack of confidence. I know it’s neither, but I don’t know what’s wrong.
It’s really hard to explain, because I don’t know what it is. And this probably doesn’t make any sense, but this is the closest I can get to talking to anybody about it.

I feel like I’m trapped, like I’m in my body, but not really. Like I can just watch, kind of take in what’s going on, but I’m not really in control… The control kinda fluxuates throughout the day, sometimes my mind is crystal clear, sometimes I feel like I’m sludging through mud.

I feel ridiculous. I don’t know what my problem is. I don’t know what I expect by putting it out here. Maybe some answers? Some tips for loosening these “ropes” I don’t know where came from? If that’s possible?