Lacking confidence!?

i was always a quiet kid in primary school but when i went into secondary school it got worse. i am now in my 4th year and i don't talk to most people. they speak to me and i just ignore them, i don't do it on purpose and i feel really guilty about it. when asked to speak in cl i get very anxious and panic. when a teacher (my guidance expecially) speaks to me alone i feel very anxious and can't make eye contact. i also fidget when i am nrevous. my friends regularly ask if im ok because i am so quiet. even that makes me nervous. please help me it's running me life