I've been bullied in the past by groups of kids (especially on my last day of elementary) and that has kind of left a scar on my mental health. 

Ever since then whenever I'm in public I fear that people would come up to me and attack me, if someone's behind me I feel my spine just tensing up, feeling all tingly, having hot flashes or whenever I'm surrounded by a bunch of people I get overwhelmed really quickly by the fear of not being capable of fending off against such a large amount of people. 

It affects me to the point that I struggle socializing with new people or that I shut down during debates. 

I've been working out and am thinking of picking up martial arts to alleviate the fear and gain self confidence, but I feel like this would be a permanent scar on my mental health.