Lack of self confidence. So plz tell!

Sir /mam 5 years back when I was in 8th class I used to be normal like other people but at that time whenever I do something wrong my parents used to scold me as usual. So due to that fear I lost my confidence as whenever they gave me some work i do that work and then think a lot abt that work whether I have done it right from inside of inside I knew it was right but due to that fear I think again and again whether u have done it right . This problem increased day by day and in all the  work. I forcibly think of past and think of small things and keep myself tense. Due to that I was mentally affected and I kept on doing things wrong bckz of tension. Moreover bcoz of tension I became thinner and thinner.my face went inside near lips . I did lot of meditation. But all in vain.due to that whenever someone instruct me something to do . I become afraid that if I will do that wrong people will laugh and what they will think . Mam plzz I can't afford to take a online suggestion. So plzz tell