What does your cardio workout look like? with the weights, do you focus on one muscle group or a whole body work out?
in regards to diet, make sure your eating healthy and often. 5-6 small meals a day. post what your diet is and there are many of us on here that can offer suggestions.
Vary your cardio, at least one day for distance, one day for speed and several days in the middle. with weights, you gotta lift, all i can say is push yourself. there is more about weight lifting than i can put on this reply