Assuming you are doing everything else right you seem like you are right on the tail end of your novice LP. As such you have a few options (I know, scary to a novice is this concept of choice). Sometimes one top set followed by 2 back off sets works for a couple weeks. Alternatively you could go into intermediate programming such as a four day split or HLM. How old are you?
Intermediate and Advanced Training: A Few Ideas | Mark Rippetoe