My Boyfriend Used To Compliment Me But Now All He Does Is Criticize Me. Does He Feel Inferior?

The reason is one of two, either he has lost all interest and is currentley getting it on with someone else or the man has lost the sight in his eyes and he is to ashamed to tell you. But no it is not because he feels inferior.

I think that at one stage or another, almost all boyfriends get like this.
When the relationship it is in its first stages, it is a little rocky, and so through constant compliments, your boyfriend is making sure that you know how much he likes you, and increases the chance of a longer relationship.
However - If he is harshly critisizing you, then you really should reconsider your relationship!
It can sometimes be due to an inferiority complex, where maybe he sees you spending more time with your friends and he wants more attention, or he is worried that you will dump him soon and so he starts putting his worries and anger onto you.
It could also be that he has found someone else and feels guilty about it, and possibly angry with himself, so he is again projecting his feelings onto you.
Whatever his reasons, talk to him about it and tell him it's upsetting you.
However, please if his criticizms turn really bad, then you should get out of the relationship as soon as you can!

Goodluck :)