Energy drinks drank on an empty stomach will GREATLY spike cortisol levels. Cortisol is a stress hormone and very catabolic of muscle tissue. Drinking that many energy drinks per day is not a good idea to begin with, especially on an empty stomach.
Eat a small meal of a high quality protein source and complex carbohydrate source 60-90 minutes before your workout. Something like a can of tuna, a bowl of oatmeal and a banana. 30 minutes before your workout take 3 pills of D-spark from n2bm.com + a b100 vitamin + a small cup of coffee. I promise that you will have much better energy throughout your workout, no crash, and will get much better results from your weight training session.