Hello thanks for your approach to us, I appreciate your self concern to handle the situation.
Feeling of insecurity is quite common for most of them, let it be relationship, studies, performance, self look, skills and others. Sometimes comparing with others in most of these areas could build up this emotion. Like the same how you are experiencing, it might be because of expectations, lack of confidence / self belief, happiness or satisfaction.
Its ok you try working on your strengths, trust yourself saying I have the ability / skills try to explore & perform in different manner, or in small work which you feel confident, understand everyone are different / unique in their own sense. Tiny success is ALWAYS VALUABLE, Keep a short term goal (weekly), Try recognise your small achievements, motivate yourself/ appreciate that you could do something.. This will help you to handle your emotions or negative thoughts.
Simultaneously try to take help of the counsellor. Take care, stay positive.
Next Steps
Along with this working yourself, visit psychologists for better guidance.
Health Tips
Keep routine and exercise, you chant omkara with help of few app or sites in the net. Help to relax, hobbies and play games with your family and friends, socialize rather staying alone.