Aside from the dietary issue, this could very well just be a case of overtraining and fatigue. Correct me if I'm wrong but you've really only started hitting the cardio hard over the last month. Give yourself time to rest and recover and your body time to adapt to the new workload before piling on more work. This is one of the hardest lessons for newer folks. Ask Chef. I had to beat this into his head for months before he got the lesson. If I was you, I would take a day or two off to rest and then resume the cardio at either a lower intensity or cut the duration back a bit until you feel fresh again.