Toooo clingy??

So I've noticed lately that I've been super clingy with my SO, to the point where I get bugged when he's just out with his friends.
In the beginning (been together two years) I was never like this, it was that but now I just feel needy and want all his attention. 
Any advice? 
Should I continue keeping it to myself, tell him about it? Is there any reason for me to be like this?