First, I'd increase your protein intake. A little piece of chicken and a couple slices of turkey just isn't enough. Eat more meat.
Second, more work isn't better work; better work is better work. Check out some routines here for some good ideas on workout setup and good progression schemes. Working out more isn't always the answer.
Lastly, diet will have a better impact on weight loss than just increasing cardio. Use cardio for staying in good health and condition. Use diet to manipulate you body composition.