Approved Posts??

Hi there, I just joined this forum the other day and started a thread in one of the sections. Every time I got to post it says a moderator needs to approve my posts which one mod eventually did so. Since then none of my posts have been approved today? Can anyone tell me why this is? It wouldn't be because I posted more than once in the thread would it? Also how long do you have to post for before your posts don't need to be approved all the time?