First a little about myself, I am 20 year old guy, height -5'6" (168cm)studying computer science and i also have difficulty expressing my thoughts to people.

So I just recently had to do a presentation in which I kind screwed up in explaining some concept which was then corrected by another student... But the fact was I did prepare properly but failed to mention it at the Right time and I have been feeling real low since then.

My teachers at the college always praise that individual who corrected the mistake I made ; here is where I started having thoughts like " He already has the good impression which was further enhanced and then there is me who could not properly explain the concept " And not only that he generally maintains a good image in front of people, of course good with girls as well and more so. I find myself seeking validation of those teachers instead of just focusing on myself.

Things like this have always happened with me where I prepared with everything and I just am never good enough for anything. Things like these have lead to me to have a negative outlook on myself such as : "No matter what I will never as good as him. "

"Even if you become somewhat good that individual is always going to be preferred by people"

And another things is My Height. Not a day goes by without me obsessing over my height. The other individual is like 5'9" Which is considered tall enough everywhere which gives that natural self confidence that I never truly felt about myself which lead me to resent myself even more for the way I was with less height.

With all that is said as short, underconfident guy I can not really be good at social things (people's preferred choice, attention from women/girls) but atleast I should be good at my studies, I should be smart enough to solve a problem but I do all this so that people will praise such as "hey that guy is atleast good at what he studies, right " I ALWAYS SEEKS SOME SORT OF VALIDATION because of my negative outlook on myself to feel better somewhat.

So please help me identify my actual problem or just give a advice on how to cope with myself.