Hi... I'm not as experience as you(only 21yrs) but I just wanted to add something...
In my opinion,you have become even more depressed when you have seen the qualifications of your collegues on that blog...
I would like to tell "you should never compare yourself with other as it is an insult to yourself"....My tutor once told us this in class and I think it is true... By comparing yourself to those ahead of you, it is normal that you will feel small and unhappy... Be what you are and be happy with what you have....
Until you do not convince yourself that you are as able as your collegue,you won't be able to move... I understand you perfectly but you have to do it...
Another thing is that they may be better qualified but thats not all you know...Often in school,colleges and universities: Some teachers may be very qualified but they don't know
1)how to pass on their knowledge...
2)they do not have good manners /their way of talking is not good
3)they are not models
Well your qualification may be not as high but I'm sure you have other qualities...
Just don't care about your them and focus on your work.
Concerning your juniors never let them know about your depression....
And if possible try to be punctual and don't be absent too many days as they will turns it against you saying that you are inefficient... Don't do anything that they might use against you...
Hope I have been able to help you...