confused... star by my name...?

Those stars indicates that how good your contribution to this site till now, in short, it displays your reputation here.

the number near your user name is your reputation, which is shown after you complete 100 posts, it is when people rate you + or - for your responses and discussion if people will rate you negative then you rating lower like your rating is 8 it will go to 7 and if people will rate you + then your rating will increase like now your is 8 then you will get 9