Hey m8, we seem alot alike
I'm still that guy, dont think i changed or anything, but the fact is, unless you break the ice, you'll stay under it forever 
What i'd recommend for that "stage fright" aint any of those silly things like go and say hi to random girls. Srsly, if i could do that, i would've aswell talked to them, ye?
So what i find a good advice, that sure helped me, is: Gather up some friends, go out, find a karaoke bar, and sing the songs u suck the most at. Works a charm, and after a drink or two, you wont feel stupid
Anyways, just pm me if u wanna talk to someone that is/was in the same mess